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Bren2010

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  1. Hey fellows, This guy seems to have the10mm bug bad. http://10mmautocombat.wordpress.com Looks to be using a Lage upper on a Mac-10 lower but built to a carbine. Check out his ammo page! Has video of 135's at 2000fps +.
  2. I have had no problems Whatsoever in my Witness 10mm. I do avoid the "wonderfinish guns" and have taken steps to reduce slide battering. The most important mod was going to the 4 3/4 slide with the Supersight and the 18 lbs spring from Wolff. The metal seems to be more like tool steel and less like ceramic. Glad you are ok.
  3. Optimizing the Witness magazine for the Bren Ten or any 10mm Currently we are operating under the constraints of Vltor in that we have not seen any frames, parts or other Bren Ten specifications for Two years. Even some of the “officially” posted material is contradictory. Thus I am working only on theory and unable to shoot my experimental magazine. Despite this, I have been playing around with Witness magazines trying to devise the best magazine for carry. I have been purchasing springs, bases and followers in an attempt to find a combo that is firm, reliable and worry free. As you may be aware, I am also an advocate of the two gun school of weapons, a Daisho which is Japanese meaning “Large/Small” in reference to the long sword “Katana” and the short sword “Wakizashi” carried by the Samurai. I believe that a Pistolman should carry a backup weapon rather than extra magazines, as the weight is the same but the utility of a second weapon is higher. Further a reliable magazine in the gun is protected from dirt and damage as long as it is contained in the gun. I currently carry a Glock 29 as my BUG (Back Up Gun) and intend to make the BrenTen my main weapon. To that end, a reliable magazine configuration based on the aftermarket seems to be vital as the Witness weapon is plagued with a reputation of jams due to magazine issues. The first part of my research was centering on reading the complaints by Witness owners on various gun blogs, trying to get a fix on where were the main complaints about the magazine centered. The second part was talking with those who used the magazine for competition to see what fixes the aftermarket had come up with. Two major jam types were immediately apparent. The first was a propensity for the magazine to allow the rim of the upper cartridge’s rim to catch on the extraction groove of the cartridge below it. When the slide slapped the upper cartridge to force it into the chamber, the tip of the bullet of the cartridge would nosedive into the feeding ramp, causing a failure to feed. The second problem was a propensity for the magazine follower to “stick” in the magazine body. The cartridges would not be lifted into position in time to be fed into the chamber and a failure to fire would result. Further, the factory magazine spring is cheap and quickly takes a “set”, which only increases the sticking problem. Trouble free magazines would gradually become “sick” and the automatic fix was to replace the spring with a stronger one. While this would sometimes cure the second problem of sticking, it would often bring about the first! Both of these problems can be directly traced to the follower, a part the factory replaced once with an “improved” design that was supposed to lessened jams of the first follower design. Frankly, it sucks. The design is a flat design with four long protruding legs down from the main part of the follower that catch on the spring as it compresses. Further, it is so tall that it sticks when the follower expands to fill the wider part of the magazine body. The design does not have a retention hole so the top loop of the spring can rest flat to the spring, so if the follower is “off” in reassembly, it can cause a problem where none existed before. The design is a second generation fix that reduces the number of cartridges and also seems to throw off the cartridge seating so much that a full magazine “rattles” when shaken and the cartridge count sight holes are off. Also, what also needed to be addressed was the overall quality of the magazine. While the body of the magazine is good steel, the floorplate is cheap plastic. These have been known to unload themselves by bursting the floorplate outward, followed by the spring, rendering the magazine useless. (Surprise!) So given these deficits, I set about curing them. The follower was the most important, as nothing else would matter if the follower still sucked. I talked with Henning Wallgren at www.henningshootsguns.com who competes with Witness guns. His advice was to use a Grams follower and one of his stronger springs. His emphasis was on the additional number of rounds that could be fitted in the magazine. He acknowledged that the factory mags sucked, but has had success rebuilding them. He also sells floorplates of machined aluminum that fit on the Witness magazine. We talked about what parts I would need and I ordered some. His shipment arrived in a few days consisting of (1) an Wolff overpower spring, (2) a slightly extended floorplate and (3) a Grams follower. The Wolff spring was far higher quality than the factory unit and the machined floorplate was perfection itself. It slid on with no issues, looked factory and made magazine changes and carrying much easier as it is rounded at the bottom rather than square and sharp. Further, this unit would not shatter if dropped on the ground. One down, many to go. The Grams follower did not help the situation. The problem with the Grams follower is that it is nearly flat, so rather than guide the rounds up the tube, it wobbles as the follower lays flat like a plate on a spring. It increases capacity and does not stick within the mag tube, curing one problem, but does not address the other which is setting the cartridges up in a way that they feed from the magazine without catching on each other. Followers: Stock 10mm Witness, Grams, Glock 29. Notice Alignment hole in Glock follower. Follower is centered fore and aft by the spring itself. Whenever I am stumped, I always like to go back to first principles. I had addressed the irritating parts of the magazine without curing the real headbanger, the feeding issue. Then I had an inspiration! Why not look at a dead reliable magazine and see how other designers had solved the problem! I had a extra 10mm magazine for a Glock 29 in my inventory so I took a look at their follower. Glock 29 Follower is braced fore and aft by hole for spring tail as well as two posts. Interesting. The Glock follower seemed to be a comprise design between the Witness 2nd Generation design and the Grams follower. Unfortunately the Glock follower is 0.2” or so too wide at the back because it is made for a wider magazine. So out came the file. This was a simple matter of taking off a little and getting the rear of the follower to “lift”. Each pass of the file got me closer to the right amount. At first the cartridge (Only one in the magazine) was pointed to the sky and was not even touching the guide lips of the magazine at all. Gradually it shifted as I ground the rear and sides narrower and narrower till it fit perfect. After 15 or so passes I got pretty good at disassembling and reassembling that magazine. DO NOT REMOVE TOO MUCH, as then you have the same problem as the grams follower. You want guidance from the follower, just set up for a narrower magazine. Final Reassembly. Victory! I could insert 15 cartridges into the magazine and they would not make a sound inside the magazine when shaken, all the cartridges pressed evenly on the feed lips of the magazine from first to the last, the material of the Glock follower did not stick in the magazine tube at all and the cartridges could be removed from the top of the magazine with a gentle push and the next cartridge would “jump” into position without complaint or delay. Interestingly, the cartridges also now aligned with the sight holes properly. I still intend to NP3 plate the magazines once they prove reliable, but I may just be gilding the lily. 15 Rounds of Doubletap 165 grain POWER. Note Mag Holes showing 9 and 15 rounds, perfect cartridge alignment on feed lips of Mag, Hemmings Base Pad. This magazine fed 300 rounds without stop, when before it wouldn't even eject the cartridges from the magazine, or if the follower stuck they could be "poured" out, with the follower jammed halfway down the tube! Materials To “Fix” a Witness Magazine 1. Glock follower for 10mm 2. File 3. Wolff Spring extra Power Magazine Spring (10 Coil) 4. Hennings Aluminum Basepad (520 or 550) 5. Safety glasses (Not Kidding) I will post pictures on Monday when I can get my tripod out of storage.
  4. Hot Rodding the Winchester 10mm Silvertip® Or Building Cool Ammo in Anticipation of the Fortis Release by Vltor The Winchester Silvertip® cartridge lineup holds an enviable position as one of the most respected series of bullet designs for self defense. In particular, the 10mm version is a slick feeding hollowpoint with a reputation of nearly 90% one shot stops. The 10mm Silvertip® is rated at 1290 fps from the factory with a 175gr bullet. Recently, there have been a few complaints about this round. Shooters are finding that the factory specs are not reflective of what they chronograph when they fire the round, especially out of a Glock 29. Also, Stopping Power, an area that Silvertips are rightfully famous for excelling in, is seen to “fall off”. Expansion in short barrels is not what should be expected of a Silvertip®. What gives? History Except for specialty manufactures like Cor-bon or Doubletap, most 10mm ammo manufacturers have downloaded the 10mm to a 40 S&W level, disparagingly referred to as “10mm lite”. This is in reverse of traditional revolver loads, where ammunition manufacturers were constantly seeking a higher velocity and power. The high power and pressure 10mm is hard on semi-auto guns, beating guns and accessories that are not designed for maximum endurance. The 10mm performance was at its peak with the original Norma factory loads, driving a 200 grain JTC slug at a clocked 1200+ fps and a 170gr hollowpoint at 1300fps. When Winchester decided to come out with a 10mm Silvertip®, the designers choose for the 10mm a similar hollowpoint design as the 44/41 Magnum Silvertips® rather than the 45 ACP or the 44 Special Silvertip® designs, probably as the 10mm at full power has far more similarity in pressure and velocity to the revolver magnums. (See Photo’s #1 and #2) Though it is difficult to tell without a caliper between the 10mm and the 44 Magnum Silvertips®, the 44 Special Silvertip® and the 45 ACP Silvertip® are radically different hollowpoint designs, reflecting their parent cartridges low pressure and velocity. The .44 Magnum 210gr Silvertip® and the 170gr .41 Magnum Silvertip® are chronographed out of a 4” vented barrel to give similar results as a defense revolver with its barrel/cylinder gap. In a legal hunting handgun length for most states (6”) these bullets exit the barrel at or above their rated speed of 1250fps. However, the 10mm Silvertip® was developed using a 5.5 inch non-vented barrel, a barrel length longer than has ever existed in Combat production guns. Combat barrel length for most Auto pistol barrels typically being 5 inches, with many a good deal less, such as 4.6” (Glock 20) or 3.78” (Glock 29). Further, numerous tests have shown that this is an optimistic muzzle velocity even in a full length gun, as the 10mm Silvertip® actual muzzle velocity exits in the lower 1200’s or even 1190’s out of a 5 inch gun in independent tests. The situation gets even worse with a short barrel like the Glock 29, with muzzle velocities posting an anemic (for the 10mm) 1129 fps. This is a total reduction in velocity of 161 fps from the printed specs! The irony is that this is also slower than the DoubleTap 40 S&W 180gr loads in the same barrel length. While the 40 S&W power is being increased by Ammo Manufactures to 10mm specs to get more stopping power and turn it into the 10mm, the 10mm has been downloaded to 40 S&W levels by some factories to make the gun more comfortable to shoot. We truly have come full circle. Concentrating now on the 175gr 10mm silvertip bullet; in actual shootings it has been shown that recovered expansion diameters are smaller, penetration is increasing and stopping power is falling off in short barreled guns (See chart #1). If only one of these factors were documented, I would say that there is a likelihood that this is a statistical fluke given the size of the test sample, but the trend is coherent for all three factors simultaneously, with the only adjusting factor being barrel length. The velocity loss in any barrel length is consistent over several studies and the Author’s own test equipment. In sum, what appears to be happening here is that the design for the Silvertip® bullet in 10mm was chosen from the magnum designs (.41 and .44 Magnum) and this design works beautifully as long as there is sufficient velocity for the bullet to open up. Combine the speed reduction with a shorter barrel and it appears that this bullet is on the ragged edge of not expanding. 10 mm Stopping Power Heavy bullet weights Brand Bullet Shootings One Shot Stops Percent Diameter Penetration Notes Winchester 175 gr ST 64 56 88% 0.76" 10.8" Winchester 175 gr ST 28 24 86% 0.69" 12.4" 4" barrel or less Federal 180 gr HS 57 49 86% 0.66" 12.9" Federal 180 gr HS 19 16 84% 0.61" 13.2" 4" barrel or less Federal 180 gr JHP 45 38 84% 0.68" 13.4" Federal 180 gr JHP 11 9 82% 0.63" 13.9" 4" barrel or less Winchester 180 gr JHP 59 48 82% 0.63" 14.6" Remington 180 gr JHP 48 29 81% 0.67" 13.7" The Handloading Cure! Happily the Winchester 10mm Silvertip® is available for reloaders in two bullet weights, one is in 155g intended for the 40 S&W and the 175 grain for 10mm. Though the 155 grain bullet is tempting, for this experiment I am sticking to the 175 grain bullet intended for the 10mm as the sectional density is better. Dusting off my reloading manuals, I find quite a few loads for 180grain and 170 grain bullets that will work for the Silvertip®. I have to reference the closest common bullet weights due to the fact that even Winchester does not have a recommended reloading chart for their own 175 grain bullet in 10mm! Looking at both Bren-Ten.com and Glock talk for powder advice plus a variety of reloading manuals, I see that the three powders that stand out for pushing heavy bullets is Accurate Arms powders #7 and #9 and IMR 800-X. Also these powders are either close to or at a compressed case fill, thus helping protect against bullet setback. As I wanted to get the maximum burn and as little flash as possible out of this loading plus protection from recoil bullet pull, I rolled a cannelure onto the 10mm Silvertip with a Corbin cannelure tool. This would allow me to use the StarCrimp® crimp I have invented. See photo #3. First the AA #7 Published Results from Glock talk. G20 with 5" KKM barrel, Doubletap Nickel cases, CCI standard primers, 180 gr Win FMJ, COL @ 1.25" 1) 12.0gr AA#7, Avg: 1288 Std Dev: 10 Hi: 1305 Lo: 1277 2) 12.3gr AA#7, Avg: 1324, Std Dev: 11, Hi: 1334, Lo: 1308 (Perfect Load) 3) 12.6gr AA#7, Avg: 1365, Std Dev: 16, Hi: 1395, Lo: 1346 This looks like a dang perfect loads, with 12.6gr being a bit too much. The 12.3 AA #7 is right on the edge of losing the low standard deviation variance that signals an inherently accurate load and is a MAX pressure load. The same load with 175 grain bullet rather than the 180 might give us 1300 average out of 12gr even. Perfect! The Accurate Arms Reloading Manual Lists the following loads: AA #7 powder using the Nosler 170gr Hollowpoint 12gr for 1305fps out of a 5” barrel. This load is listed as MAX, so start 2gr lower. For AA #9 the 170 grain Nosler is pushed with 15 grains of powder MAX for 1341 fps and 180 grain Speer the AA#9 load is 14.5 grains MAX for 1290. I would start using the starting loads for the 180gr bullet and work up to 1300fps or 14.5gr Max for the 175 Silvertip. This represents a great powder for those who want to prevent bullet setback, as the powder is compressed, no setback is possible. AA#9 may represent the best powder for reloading on a progressive press as it meters so well. Moving to 800-X, Mike McNutt of DoubleTap has this load published on Glock 10mm Forums: Nosler Jacketed HP 170 800-X 10.6g (Comp) 1.250" 1350fps Avg 688fpe avg. He advises that you start 2grs lower than his loads and work up watching out for pressure signs and a fully supported barrel. Different barrels and different brass will show different reactions and pressure levels. Please note this is much faster than we are looking for! For a short barrel he publishes the 10.6gr load for a Hornady 180XTP bullet. 10.8grs of 800X gives 1263fps out of an AFTERMARKET 3.78 Glock 29 barrel. The Silvertip might give 1300 flat! Please note that these are all OVER max loads recommended for experts by experts. Use the reloading manual data if you are unsure what you are doing or see signs of high pressure! IMR data recommends a lower charge of 9.7grs MAX for 800-X for 1320fps and low pressure of 34,200PSI for a 180gr bullet from a 5” barrel, so this charge seems to combine speed, fill, and low relative pressure like AA #9. Unhappily, each load must be hand weighed as 800x meters very poorly and you risk very high pressures if you try to use a powder measure, which removes it from ease of mass production. Astonishingly, IMR does not list a starting load, but I feel that a range of 9.5gr to 10.0gr of 800-X will give me 1300fps for the Silvertip. I might even back down a little if less than 10.0grs gives me 1300fps. Overall, AA #9 appears to be the best powder for 10mm. With its 100% fill to prevent bullet setback, its ease and consistent metering, the impossibility of overcharging the cartridge, the cleanliness of the powder, low terminal pressure and the high velocity achieved, this powder may represent the perfect blend of characteristics. Using the Starcrimp® to prevent bullet pull due to recoil a totally rugged cartridge is produced with high velocity. Remember, the goal is not to build the most screamingly hot, brass destroying, primer busting, gun breaking load possible, the goal is to bring back the 10mm Silvertip into its operating envelop within a 5 inch barrel.
  5. It sounds like you are going the right way. You have increased the mass of the upper as far as possible without going to exotic stuff like a Clark Scope mount and you are using good material. I would use a reasonable spring for recoil, like 20 lbs to start and see how it feels. In this case, I would use as little spring as possible and a buff as necessary. Use a stiff Firing pin spring.
  6. It appears that there has been a limited run of Grips made for the Bren Ten Pistols!! See Bren Ten Forum under the section "Bren Ten 10mm and 45 ACP's" under the heading "Plastic Sucks". The Pictures are Eye Popping! For all those who own these pistols, this is a really nice upgrade accessory!!
  7. "Daisho" carried daily consisting of: 1. Bren Ten Standard Model 2. Bren Ten Special Forces "Amiegil" (Meaning Short Sword or Little Friend):
  8. I agree! I would use the ramped Bar-Sto barrel, but I also would go with a bull barrel, which will slow slide speed and unlocking. Once fitted, this would be a excellent weapon for full power carry. I have long considered getting an LDA P-16 for just such a conversion. Bar-Sto barrels are "Quality Extraordinaire" and heavy enough to do what you want. Another alternative is the SVI Infinity barrel (Scheuman?) which have a better twist and even have progressive twist. Either choice will give you a lifetime of accuracy and power unparalleled by 45 ACP.
  9. I had the same thing happen with my Ar-15 in 10mm, also with an Oly Upper. I had taken it out for the first time to sight it in. I had a miss feed, and I cleared it and cycled the next round in. Pulled the trigger and BANG. My case looked just like yours. Case was a new DoubleTap Nickle case with a warm load of 800X and a Silvertip bullet. Bullet was stuck in the barrel about two inches from the front of the chamber. Cartridge had "Skirted" just like yours. As a reminder to always wear safety glasses I have hung the cartridge case up over my computer and I am looking at it as I write. I went through the gun and found I had a badly reamed chamber. First I checked headspace in it, which was perfect, then I got hold a a finishing reamer with a hand T handle and gently turned it a couple of time to remove any high spots but did not ream deeper. I then polished the chamber with some polishing compound (A b**** of a job) till the chamber was mirror. I also increased the recoil spring strength. 350 rounds and no further problems. In fact, the ejection is smoother and looks more positive, ejecting straight out from the receiver at 90 degrees and gets tossed about 5 feet. I use my carbine as Thug repellent, so it has to work.
  10. Astonishing how similar the cracks appear to the stress analysis done by Vltor on their computer. They posted the picture on their website (since taken down) of both the slide and frame under maximum stress and these cracks look exactly like that analysis.
  11. It is a great round. Just picked up some 165 Golden Sabers. Nasty looking round.
  12. There is no such thing as 10mm +P. 10mm has a strict pressure limit and that limit should be respected.
  13. Thank you for the vote of confidence. I agree that ammo makers are screwing us for the price of ammo, but what can you say? I have winnowed my "armory" down to three calibers, 10mm, 308, and 44 Mag. All three easily adaptable to Urban war, hunting, and self defense. (22's as well) I use 10mm in place of 223 as I can equip myself with a 10mm pistol carbine that will do all a 223 will do AND fit in a sidearm. I thank you Taos for the info on the Silvertip and AA#9 and Elite Ammo. When the ghettos erupt, what can I say but "Good Hunting" Gentleman.
  14. Hot Rodding the Winchester 10mm Silvertip® Or Building Cool Ammo in Anticipation of the Fortis Release by Vltor The Winchester Silvertip® cartridge lineup holds an enviable position as one of the most respected series of bullet designs for self defense. In particular, the 10mm version is a slick feeding hollowpoint with a reputation of nearly 90% one shot stops. The 10mm Silvertip® is rated at 1290 fps from the factory with a 175gr bullet. Recently, there have been a few complaints about this round. Shooters are finding that the factory specs are not reflective of what they chronograph when they fire the round, especially out of a Glock 29. Also, Stopping Power, an area that Silvertips are rightfully famous for excelling in, is seen to “fall off”. Expansion in short barrels is not what should be expected of a Silvertip®. What gives? History Except for specialty manufactures like Cor-bon or Doubletap, most 10mm ammo manufacturers have downloaded the 10mm to a 40 S&W level, disparagingly referred to as “10mm lite”. This is in reverse of traditional revolver loads, where ammunition manufacturers were constantly seeking a higher velocity and power. The high power and pressure 10mm is hard on semi-auto guns, beating guns and accessories that are not designed for maximum endurance. The 10mm performance was at its peak with the original Norma factory loads, driving a 200 grain JTC slug at a clocked 1200+ fps and a 170gr hollowpoint at 1300fps. When Winchester decided to come out with a 10mm Silvertip®, the designers choose for the 10mm a similar hollowpoint design as the 44/41 Magnum Silvertips® rather than the 45 ACP or the 44 Special Silvertip® designs, probably as the 10mm at full power has far more similarity in pressure and velocity to the revolver magnums. (See Photo’s #1 and #2) Though it is difficult to tell without a caliper between the 10mm and the 44 Magnum Silvertips®, the 44 Special Silvertip® and the 45 ACP Silvertip® are radically different hollowpoint designs, reflecting their parent cartridges low pressure and velocity. The .44 Magnum 210gr Silvertip® and the 170gr .41 Magnum Silvertip® are chronographed out of a 4” vented barrel to give similar results as a defense revolver with its barrel/cylinder gap. In a legal hunting handgun length for most states (6”) these bullets exit the barrel at or above their rated speed of 1250fps. However, the 10mm Silvertip® was developed using a 5.5 inch non-vented barrel, a barrel length longer than has ever existed in Combat production guns. Combat barrel length for most Auto pistol barrels typically being 5 inches, with many a good deal less, such as 4.6” (Glock 20) or 3.78” (Glock 29). Further, numerous tests have shown that this is an optimistic muzzle velocity even in a full length gun, as the 10mm Silvertip® actual muzzle velocity exits in the lower 1200’s or even 1190’s out of a 5 inch gun in independent tests. The situation gets even worse with a short barrel like the Glock 29, with muzzle velocities posting an anemic (for the 10mm) 1129 fps. This is a total reduction in velocity of 161 fps from the printed specs! The irony is that this is also slower than the DoubleTap 40 S&W 180gr loads in the same barrel length. While the 40 S&W power is being increased by Ammo Manufactures to 10mm specs to get more stopping power and turn it into the 10mm, the 10mm has been downloaded to 40 S&W levels by some factories to make the gun more comfortable to shoot. We truly have come full circle. Concentrating now on the 175gr 10mm silvertip bullet; in actual shootings it has been shown that recovered expansion diameters are smaller, penetration is increasing and stopping power is falling off in short barreled guns (See chart #1). If only one of these factors were documented, I would say that there is a likelihood that this is a statistical fluke given the size of the test sample, but the trend is coherent for all three factors simultaneously, with the only adjusting factor being barrel length. The velocity loss in any barrel length is consistent over several studies and the Author’s own test equipment. In sum, what appears to be happening here is that the design for the Silvertip® bullet in 10mm was chosen from the magnum designs (.41 and .44 Magnum) and this design works beautifully as long as there is sufficient velocity for the bullet to open up. Combine the speed reduction with a shorter barrel and it appears that this bullet is on the ragged edge of not expanding. 10 mm Stopping Power Heavy bullet weights Brand Bullet Shootings One Shot Stops Percent Diameter Penetration Notes Winchester 175 gr ST 64 56 88% 0.76" 10.8" Winchester 175 gr ST 28 24 86% 0.69" 12.4" 4" barrel or less Federal 180 gr HS 57 49 86% 0.66" 12.9" Federal 180 gr HS 19 16 84% 0.61" 13.2" 4" barrel or less Federal 180 gr JHP 45 38 84% 0.68" 13.4" Federal 180 gr JHP 11 9 82% 0.63" 13.9" 4" barrel or less Winchester 180 gr JHP 59 48 82% 0.63" 14.6" Remington 180 gr JHP 48 29 81% 0.67" 13.7" The Handloading Cure! Happily the Winchester 10mm Silvertip® is available for reloaders in two bullet weights, one is in 155g intended for the 40 S&W and the 175 grain for 10mm. Though the 155 grain bullet is tempting, for this experiment I am sticking to the 175 grain bullet intended for the 10mm as the sectional density is better. Dusting off my reloading manuals, I find quite a few loads for 180grain and 170 grain bullets that will work for the Silvertip®. I have to reference the closest common bullet weights due to the fact that even Winchester does not have a recommended reloading chart for their own 175 grain bullet in 10mm! Looking at both Bren-Ten.com and Glock talk for powder advice plus a variety of reloading manuals, I see that the three powders that stand out for pushing heavy bullets is Accurate Arms powders #7 and #9 and IMR 800-X. Also these powders are either close to or at a compressed case fill, thus helping protect against bullet setback. As I wanted to get the maximum burn and as little flash as possible out of this loading plus protection from recoil bullet pull, I rolled a cannelure onto the 10mm Silvertip with a Corbin cannelure tool. This would allow me to use the StarCrimp® crimp I have invented. See photo #3. First the AA #7 Published Results from Glock talk. G20 with 5" KKM barrel, Doubletap Nickel cases, CCI standard primers, 180 gr Win FMJ, COL @ 1.25" 1) 12.0gr AA#7, Avg: 1288 Std Dev: 10 Hi: 1305 Lo: 1277 2) 12.3gr AA#7, Avg: 1324, Std Dev: 11, Hi: 1334, Lo: 1308 (Perfect Load) 3) 12.6gr AA#7, Avg: 1365, Std Dev: 16, Hi: 1395, Lo: 1346 This looks like a dang perfect loads, with 12.6gr being a bit too much. The 12.3 AA #7 is right on the edge of losing the low standard deviation variance that signals an inherently accurate load and is a MAX pressure load. The same load with 175 grain bullet rather than the 180 might give us 1300 average out of 12gr even. Perfect! The Accurate Arms Reloading Manual Lists the following loads: AA #7 powder using the Nosler 170gr Hollowpoint 12gr for 1305fps out of a 5” barrel. This load is listed as MAX, so start 2gr lower. For AA #9 the 170 grain Nosler is pushed with 15 grains of powder MAX for 1341 fps and 180 grain Speer the AA#9 load is 14.5 grains MAX for 1290. I would start using the starting loads for the 180gr bullet and work up to 1300fps or 14.5gr Max for the 175 Silvertip. AA #9 represents a great powder for those who want to prevent bullet setback, as the powder is compressed, no setback is possible. AA#9 may represent the best powder for reloading 10mm on a progressive press as it meters so well. Moving to 800-X, Mike McNutt of DoubleTap has this load published on Glock 10mm Forums: Nosler Jacketed HP 170 800-X 10.6g (Comp) 1.250" 1350fps Avg 688fpe avg. He advises that you start 2grs lower than his loads and work up watching out for pressure signs and a fully supported barrel. Different barrels and different brass will show different reactions and pressure levels. Please note this is much faster than we are looking for! For a short barrel he publishes the 10.6gr load for a Hornady 180XTP bullet. 10.8grs of 800X gives 1263fps out of an AFTERMARKET 3.78 Glock 29 barrel. The Silvertip might give 1300 flat! Please note that these are all OVER max loads recommended for experts by experts. Use the reloading manual data if you are unsure what you are doing or see signs of high pressure! IMR data recommends a lower charge of 9.7grs MAX for 800-X for 1320fps and low pressure of 34,200PSI for a 180gr bullet from a 5” barrel, so this charge seems to combine speed, fill, and low relative pressure like AA #9. Unhappily, each load must be hand weighed as 800x meters very poorly and you risk very high pressures if you try to use a powder measure, which removes it from ease of mass production. Astonishingly, IMR does not list a starting load, but I feel that a range of 9.5gr to 10.0gr of 800-X will give me 1300fps for the Silvertip. I might even back down a little if less than 10.0grs gives me 1300fps. Overall, AA #9 appears to be the best powder for 10mm. With its 100% fill to prevent bullet setback, its ease and consistent metering, the impossibility of overcharging the cartridge, the cleanliness of the powder, low terminal pressure and the high velocity achieved, this powder may represent the perfect blend of characteristics. Using the Starcrimp® to prevent bullet pull due to recoil a totally rugged cartridge is produced with high velocity. Remember, the goal is not to build the most screamingly hot, brass destroying, primer busting, gun breaking load possible, the goal is to bring back the 10mm Silvertip into its operating envelop within a 5 inch barrel.
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