geepee3

I think my 300 Blackout AR pistol should cycle fine using 1680 powder. There are difference in the loading on Hodgdon's website. Seating depth is much deeper on the 1680 sub load. 2.089" COL. as opposed to 2.260". Velocity is 25 fps. more on the 1680 sub load, 1085 vs 1060 from a 16" barrel. Pressure is 18,200 psi from the CFE Black vs 32,300 psi from the 1680 powder. Both measured with 16" barrels. So yes, almost half the psi's between the two loadings posted. Normally, with supersonic cartridges I prefer a lower pressure curve when reloading. But with subs and a shorter dwell time, I would prefer the higher pressure curve. Thanks, Glenn

Prepped, tumbled and primed 100 Gemtech 300 blackout cases for the new upper. Also tumbled what was left in my 250 ct. box of 115 gr., 30 cal. pulled projectiles made for 300 blackout. Was also double checking Hodgdon data for reloading supers and subs. Seen a few things on the interweb about 300 blackout subs not cycling in shorter length AR pistols. When I looked at the data, I noticed that CFE Black had almost half the pressure output at 16" than 1680... Makes you wonder if some of these manufacturers are using CFE Black and not creating the required pressure. I have both powders, but will be using 1680 when I put together some subs. To be honest, I need to get some 220 gr. projectiles that aren't plated. I have a bunch of the Berry's plated bullets, but they don't recommend shooting them in anything faster than a 1:7 twist. My 7.5" 300 Blackout barrel is 1:5... Oh well, prepped for everything except subsonic 300 blackout projectiles... It's always something... Thanks, Glenn

No can myself, but thinking about it. Have a few firearms a .30 cal. can would work on. So, we shall see. Thank you! Glenn

Got the upper finished off last night. Had the barrel installed on Wednesday then could not find my gas block jig and punch... Forgot that I gave my gas block jig and starter punch to my coworker to use. So, once I got the right tools for the job back, I finished the upper up after dinner. So here it is, Need to get some sights on it and put together more ammo for it. On call this weekend, so no joy there... Will get it out and give a range report. Thanks again! Glenn

Parts came in from tonight. Handguard and muzzle device. Here's the hand fitted mockup. Sharps Bros. 7" M-LOK handguard and CMMG 30 cal. ZEROED linear comp. Went and dimpled the barrel with the SLR Dimpling Jig on my drill press tonight. Having the right tools makes things quick and easy! Planning on assembling parts on Wednesday, but I might get the urge to finish off tomorrow... You never know with me... Thanks again! Glenn

Dang-it, I'm in Florida so I can't claim that syndrome... Hope you're able to get that shop up and running. Hopefully I'll have something soon for you to "ogle and Drool" over! Thanks again! Glenn

This from the guy who keeps talking about his last build four rifles ago... It is called "Blackout"... So come to the dark side my child!!! Thank you! Glenn

Why is it that the things you ordered first, come last...? So, I got the Aero Precision adjustable gas block in today. Which happened to be the last thing I ordered for this upper, by a few days. Comes in a nice box along with everything you see here. Nice that they give you an extra detent ball and spring in case you lose the original one removing the adjustment screw. Cosmetically you can see the machining marks on the top side flats. The barrel hole where it matters in nice and smooth. Has a good close fit to the gas block journal too. I'm going to need to dimple the barrel. Have the SLR jig for that. Hopefully the handguard and linear comp come in earlier this next coming week. We shall see... Thank you, Glenn

Yes!!! Pictures are always welcome! Thank you. Glenn

Not much racial diversity in that group... They should be ashamed of themselves for that! Almost all are from out of state. Special thanks to the FBI for their hard work on stopping a domestic terrorist threat... Oh wait... They didn't... Thank you, Glenn

Don't really have anything barreled from Daniel Defense, just a few of their flash hiders and magazines. Holosun specs are stated as a 2 inch MOA dot. So hopefully 2 inches or better... Depending on the ammo and driver... Would definitely like to see your set up when you get the rifle in, so please post some pictures. Thank you. Glenn

Thanks for the work you did all those years! People like me definitely benefited from your talents! In fact, I own six of your AR barrels, two of them being wildcats, the TAC 30 and TAC 6. Appreciate you making the rounds. Speaking of which, still have a hoard of the MK319 MOD0 SOST projectiles. Enjoy your retirement, you earned that! Thank you, Sir! Glenn

Thank you! And images are always welcome... Had a Faxon 9mm AR pistol barrel and BCG that worked great. Coworker ended up with that upper after my second CMMG 9mm RDB pistol upper build. Which is why I ended up with this Faxon barrel this time around. Ordered the handguard and linear comp. today. Seems most places are out of the Aero adjustable gas block. May have to try another brand. Thanks again! Glenn

Thank you! You can if you want to run subsonic without a suppressor. Just not going to be as quiet as suppressed. Big question is, was the gas port drilled out to run reliably unsuppressed. By the way, what barrel length is your 300 Blackout pistol? Thanks, Glenn

Thank you! Will have to run some test to find out, since I do have a 10" barrel with a 1:7 twist to compare it to. Mrgunsngear did a video on differences from 7.5" up to 16". He has a 10.3" DD barrel in that video. The black projectiles in the above picture is what I'm planning to run supersonic. They were projectile Mid-South sold a few years back from some failed company. They are 125 gr. projectile specifically designed for 300 Blackout. Had a gentleman from the 6.8 Forum test them a while back through wet newspaper. They should do the job, although the hydro-static shock was not as good as the other bullet tested. The 1:5 twist may help that. Thanks again! Glenn