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223 trim length


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#1 OFFLINE   lal357

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Posted Mar. 26 2009 - 08:13 PM

been looking on the net at trim lengths and found 1.750 and 1.740 so i checked a new winchester case and it reads 1.750 what do ya'll trim to.


#2 OFFLINE   TomJefferson

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Posted Mar. 26 2009 - 08:41 PM

1.760" which btw is what my Lyman's book calls for and what I have been measuring most factory ammo at.

Actual 5.56mm is 1.772"

Here's a great pdf for you to save down to your computer. Its a die/chamber drawing for both .223 and 5.56mm brass.

.223 vs 5.56mm

This gives you a lot more insight to the dimensionals. Notice the tolerances and keep in mind too long is what you are trying to avoid since it can cause up to a 10,000 psi pressure spike.

Tj


#3 OFFLINE   lal357

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Posted Mar. 26 2009 - 09:13 PM

isnt 1.760 the max cartidge length heres what i found

http://www.accuratep...i... to 187.pdf


#4 OFFLINE   rigger

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Posted Mar. 26 2009 - 10:11 PM

isnt 1.760 the max cartidge length heres what i found

http://www.accuratep...i... to 187.pdf



I trim to 1.750 and use 1.760 as maximum length as well.


#5 OFFLINE   amlevin

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Posted Mar. 26 2009 - 10:15 PM

I trim my cases to 1.755". With a Montana Gold 55gr. FMJ-BT bullet w/cannelure I find that seating to 2.250 OAL the case mouth is directly in the middle of the cannelure. I find that 2.250" not only feeds well in both my AR's the rounds yield nice tight groups. When I push 2.260" I have occaisonal stoppages due to jams in the mags.


#6 OFFLINE   creekhawg

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Posted Mar. 26 2009 - 10:53 PM

1.755 on my LC when it grows


#7 OFFLINE   TomJefferson

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Posted Mar. 26 2009 - 11:18 PM

isnt 1.760 the max cartidge length heres what i found

http://www.accuratep...i... to 187.pdf


Sorry about that link. I had to redo it. Its OK now.

Yes, 1.760" is maximum for .223, however its still 0.012" short of 5.56mm maximum of 1.772".

By doing 1.760", this allows me to sort my used brass using a caliper, which I do 100%. Most once fired brass will not exceed the 1.760" even 5.56mm so not require trimming. Converting 5.56mm brass to .223 just doesn't make too much sense especially since the bottom says 5.56mm and I'm not thinning the case to match .223. What I am basically doing is reloading 5.56mm not .223.

Twice fired brass, the percentage of brass over the 1.760" goes way up.

Tj


#8 OFFLINE   TomJefferson

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Posted Mar. 26 2009 - 11:30 PM

I trim my cases to 1.755". With a Montana Gold 55gr. FMJ-BT bullet w/cannelure I find that seating to 2.250 OAL the case mouth is directly in the middle of the cannelure. I find that 2.250" not only feeds well in both my AR's the rounds yield nice tight groups. When I push 2.260" I have occaisonal stoppages due to jams in the mags.


Yeah, I had the 2.260" COL problem when I first started shooting the MIL 62 grain ammo which depending on which type can actually be as high as 2.262" COL from the factory. A lot of aftermarket mags are designed for .223 really.

I'll have to try the Montana Golds, my HDY 55s are loading out on the cannelure at about 2.240". It makes me suspect they may have a tad better ballistic coefficient.


#9 OFFLINE   GLShooter

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Posted Mar. 27 2009 - 02:05 PM

I trim to 1.750 on all my 223/5.56's. I have found that loading to max on the magazine size does not cause feeding issues. I load 95% non-cannulered bullets and have no issues. With the cannuelered I , of course, load that lenght and have no issues there either.

I do know that most chambers will accept longer than max length cases but not all so beware of that issue. I know of a few AR's that MIGHT have self destructed because of that but it was not 100% certain but it was probably a factor.


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#10 OFFLINE   GLShooter

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Posted Mar. 27 2009 - 02:08 PM

been looking on the net at trim lengths and found 1.750 and 1.740 so i checked a new winchester case and it reads 1.750 what do ya'll trim to.


BTW what trimmer did you get?


#11 OFFLINE   lal357

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Posted Mar. 27 2009 - 04:09 PM

its just a lyman universal i had/have one in a box somewhere but for the life of me cant figure out what my did with it . i told her today (as i was buying some reloading stuff) that when i replace everything thats missing then the box will be found .
right now i'm load with the canlure forward of the crimp but my col is 2.254 (farthesst out i can load it and still be able to load in my mags) .


#12 OFFLINE   GLShooter

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Posted Mar. 27 2009 - 04:15 PM

I think you can buy a power adapter for the handle to use with a power screwdriver. I had one made for my Forster years before they were available. It sure speeds things up.


#13 OFFLINE   lal357

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Posted Mar. 27 2009 - 05:03 PM

yeah i'm looking into that i have'nt mounted it yet been thinking about making a couple of wood bases 1 for the trimmer and 1 for my powder thrower and pre drill holes in the bench to bolt them down with bolts and wing nuts. this way i can remove and put up out of the way when not in use.


#14 OFFLINE   GLShooter

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Posted Mar. 27 2009 - 05:10 PM

yeah i'm looking into that i have'nt mounted it yet been thinking about making a couple of wood bases 1 for the trimmer and 1 for my powder thrower and pre drill holes in the bench to bolt them down with bolts and wing nuts. this way i can remove and put up out of the way when not in use.


I did that for a trimmer, my Dillon Swager and the pattern for the base on an RCBS Uniflo set up that I use for short run stuff if I don't want to weigh every charge or am using my progressives at full capacity.


#15 OFFLINE   TomJefferson

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Posted Mar. 27 2009 - 05:20 PM

I trim to 1.750 on all my 223/5.56's. I have found that loading to max on the magazine size does not cause feeding issues. I load 95% non-cannulered bullets and have no issues. With the cannuelered I , of course, load that lenght and have no issues there either.

I do know that most chambers will accept longer than max length cases but not all so beware of that issue. I know of a few AR's that MIGHT have self destructed because of that but it was not 100% certain but it was probably a factor.


I don't follow you there.

If you look at that die drawing the .223 length is 1.760" - 0.020". As a drawing, that means ideal is 1.760" no higher and you can go as low as 1.740" and still in spec.

You're well within specification as everyone in this thread is really.


#16 OFFLINE   TomJefferson

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Posted Mar. 27 2009 - 05:23 PM

its just a lyman universal i had/have one in a box somewhere but for the life of me cant figure out what my did with it . i told her today (as i was buying some reloading stuff) that when i replace everything thats missing then the box will be found .
right now i'm load with the canlure forward of the crimp but my col is 2.254 (farthesst out i can load it and still be able to load in my mags) .


That's the trimmer I have. Its actually max simple. The case lock mechanism works very well and once you get the hang of the feel when the little ball pops into the primer pocket, pretty fast.

Its so simple and easy, I'm looking at powering the deburring before I do power the trimming.

I think you will like it.

Tj


#17 OFFLINE   GLShooter

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Posted Mar. 27 2009 - 05:33 PM

I don't follow you there.

If you look at that die drawing the .223 length is 1.760" - 0.020". As a drawing, that means ideal is 1.760" no higher and you can go as low as 1.740" and still in spec.

You're well within specification as everyone in this thread is really.


I was referring o the post above that mentioned if he shaded the max trim length and loaded to the cannuler he had feeding issues.

I was also mentioning that many chambers actually could accept a long case neck but this is not always true. If you have one of the Sinclair plug gauges you can check your chamber neck length and might find you don't have to trim as short as specs show. When I am fitting cases to a specific rifle I do look at this measurement. I have a 6 PPC barrel that was poorly cut (that I bought used) The chamber will allow me to let the necks go 0.025 longer than SAAMI specs. I do cut them down to 0.015 below the case neck length on this rifle but on this particular rifle. This barrel has everything out of spec so I truly am fitting the cases to the chamber.


#18 OFFLINE   TomJefferson

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Posted Mar. 27 2009 - 05:54 PM

I was referring o the post above that mentioned if he shaded the max trim length and loaded to the cannuler he had feeding issues.

I was also mentioning that many chambers actually could accept a long case neck but this is not always true. If you have one of the Sinclair plug gauges you can check your chamber neck length and might find you don't have to trim as short as specs show. When I am fitting cases to a specific rifle I do look at this measurement. I have a 6 PPC barrel that was poorly cut (that I bought used) The chamber will allow me to let the necks go 0.025 longer than SAAMI specs. I do cut them down to 0.015 below the case neck length on this rifle but on this particular rifle. This barrel has everything out of spec so I truly am fitting the cases to the chamber.


Oh sorry, I follow you.

Yes, that was what I was replying to in my other post as well. Quite a while back, I bought a couple cases of to be specific 63 grain Swiss Nato ammunition. God, this stuff is some of the finest factory ammo I ever bought. It has a very consistent muzzle velocity, well defined bullet shape, and good recoil, however its overall height actually hits as high as 2.763". It works just fine in my MIL spec mags but will will have feed issues on about every mag I have that isn't USGI. The fact they are 0.002" to 0.003" above MIL spec is probably why they were surplussed. Still I like it well enough, I put a bunch back for SHTF or special occasions. It sure shoots sweet. (BTW, the reason why they are over is the tip is really a sharp point like a Ballistic Tip not near as dull a point as say normal SS109.)

All my loadouts my longest I will go is 2.760" or max MIL spec and I only do that on my precision rounds where I'm looking to narrow the jump off to rifling gap. My COLs are all over the place depending on bullet.

My rifles are all 5.56mm and I've actually ran necks as long as 1.770" checking for pressure issues which I have found none. I wish I had used a gauge like you suggested, it would have been far simpler than the way I went about it. Anyway, I now hold my lengths to drawing ideal 1.760". I'm into volume now so can't insure the ammo will be shot up and it just may/might find its way into a .223 chamber someday. Working in brass for well 30 years now, I can pretty much hold that tolerance with a very high degree of confidence. I use probably what you guys would think very excessive statistical process control.

Besides reducing some initial trimming by holding the 1.760", I use quite a bit of that length for retention when I do ID neck sizing and go for a looser fit. I have this favorite bullet I like, 55 Nos BT, that it seems to make a difference accuracy wise if I loose fit it and to hit my repeatability its either mic the ID every time I do a setup or keep my die cranked to the loosest setting and keep my neck length right on the 1.760" mark. (Yes, I'm probably off the deep end of silliness on a semi. God knows what crazy shat I will get into on a .308?" :laugh:

Regardless, you hit a major point that often we take for granted. The strength of reloading is we can load specifically for our guns so what works for one isn't necessarily the best for others.

It sure is neat hearing about what works for folks and why though. :thumb:

Tj


#19 OFFLINE   GLShooter

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Posted Mar. 27 2009 - 06:05 PM

I pretty much neck size only on my bolt guns. I just picked up a new S type FL bushing style 223 Sizer and will be loading 223 and 6 6X45 with it for my AR's in the future. I have it for my 20 Tactical and a full competition set up for my 204's.

The Sinclair plugs were something I bought on a whim and they are the BERRIES!! LOL You have to try them out. I rarely shoot factory unless the job gave it to me like Fed GM 308 stuff or various pistol types. I reload everything that gets shot by me 99.9 % of the time. Not lazy, just cheap and I know what my stuff will do every day. I never worry about box to box variations in lots. Its all my lot.

I have gotten some instructions on how to post pics so maybe I can get some up on the board. I have lurked here for a while so now it's time to come out from under the stairs.


#20 OFFLINE   TomJefferson

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Posted Mar. 27 2009 - 06:39 PM

I pretty much neck size only on my bolt guns. I just picked up a new S type FL bushing style 223 Sizer and will be loading 223 and 6 6X45 with it for my AR's in the future. I have it for my 20 Tactical and a full competition set up for my 204's.

The Sinclair plugs were something I bought on a whim and they are the BERRIES!! LOL You have to try them out. I rarely shoot factory unless the job gave it to me like Fed GM 308 stuff or various pistol types. I reload everything that gets shot by me 99.9 % of the time. Not lazy, just cheap and I know what my stuff will do every day. I never worry about box to box variations in lots. Its all my lot.

I have gotten some instructions on how to post pics so maybe I can get some up on the board. I have lurked here for a while so now it's time to come out from under the stairs.



A little off topic, but isn't it a mind blower? I can't believe what all I have put up with over the years due to heck not just lot to lot variation but brand to brand which is even worse.

I not only think now of how much ammo I have wasted over the years just figuring out what it will do but the personal value of all the ammo I have stocked back has gone way down in my mind.

Yes, I'm heading down your path for sure.

Tj

edit: BTW, Thanks I will get the gauge hopefully before I jump off (play on words lol) to my .308 loading.





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