I have a 300blk PSA 10.5 upper on a Anderson lower. Been running fiocchi brass casing great. Started using Barnaul steel casing and it will not cycle next round. I can rack the round no problem and it ejects spent casing but will not feed next round. Running Magpul Gen 2 mag. What can I doto fix this? Thanks
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Steel cased ammo is notoriously undergassed and steel on steel has more friction than brass on steel. Less gas + more friction = cycling issues.
You’d need to get a lighter spring/buffer, open the gas port on the barrel (don’t do this), or stop using steel cased ammo.
Probably a gas issue as mentioned above. If you aren’t using a suppressor on a short barrel make sure you also arnt using subs and that you use plenty of lube.
@NOVEMBER_RUSH check out @MrFister response. Well said. Keep your rig clean and well oiled.
I have pretty close to the same setup, a little shorter barrel but pretty close. It is really sensitive to getting dirty.
Is it getting stuck on the feed ramp? Same bullet shape?
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I don’t think the bolt is coming back far enough to catch the end of the casing because it’s marking it up bad about halfway down. The gun has only about 50 rounds through it and it cycles the brass casing great. I’m building a 7.62x39 with a 7.5 barrel and I’m going to put it on the Anderson lower that’s on the 300 now and build a Stag for the 300. If that doesn’t change anything then I’m going to change the buffer tube
Changing the buffer tube shouldn’t change anything. Give us a detailed list of your set up.
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Anderson lower with psa sba3 ept lower build kit with psa 10.5 300blk upper
Are you shooting subs or just supers? Issue could be ammo related. If shooting subs you might need a lighter buffer.
Barnaul 147gr
Steel can be problematic, and Barnual steel has a polymer coating on it to prevent corrosion. I imagine it’s a little under powered also. Have you cleaned the chamber really good?
Definitely the ammo. Lacquered ammo is known to cause cycling issues because the lacquer can break off and stay in the chamber.
OK I thought that myself to coz it almost seems sticky. With that being said I know everybody hates steel ammo as do I but if you were going to run steel ammo what kind would you shoot?
@GuitarGuy @MrFister @Josiah_PSA
10.5 or 8.5 barrel for 300blk? In your opinion of course. Shooting subs and supers but usually supressed. OSS helix
8.5" the round was developed for 8-9" barrels with a can.
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FWIW… .223 / 5.56 / .300BK ( or any “straight walled” cartridge ) steel cases do not “release” from the chamber walls as rapidly as brass cases.
So the tend to require more “ooomph” to pull that still expanded straight walled steel case from the chamber walls. That is part of the reason most typical “ComBloc” ammo is tapered… less force needed to pull away from a tapered chamber, all those take is a tiny amount of movement / time to pull free.
I would suggest you ( as mentioned ) you try cleaning the chamber very well.
Can you post a pic of your fired brass case , to see if your chamber has any burrs ?
Do you know what your buffer weight is? If you’re dedicated to using steel, you could try a lighter buffer. It would probably help with cycling the lower gas rounds. It’s still odd to me, because even at that length, the upper should have a pistol length gas tube, which should provide plenty of gas…
I have a 10.5 in 300 blackout that was having the same issues. I found out that these rounds were meant to be ran suppressed. I fixed the cycling issue by drilling out the gas port just slightly larger. I’ve never had a cycling issue since. Just make sure when drilling the port hole you use cutting oil and clean it well after.
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I have no idea. All I can tell you is what I bought and it isn’t dirty it was brand new and had been cleaned before use to get ask the excess grease and oil off just like I have every other. This is the package…PSA 10.5" PISTOL LENGTH 300AAC 1/8 PHOSPHATE 10.5" LIGHTWEIGHT M-LOK MOE EPT SBA3 PISTOL KIT and I had it on a Anderson lower. I have since taken that upper and put it on a Stag lower with a new PSA MOE SBA3 LOWER BUILD KIT and I haven’t yet been able to test it out. I have put a BCA 7.5" 7.62X39 on the Anderson lower and have yet to test it and I have the same Barnaul steel case ammo for it so I’m hoping something changes if not I will have a lot of ammo for sale.
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Welcome! @NOVEMBER_RUSH @Michaelgregg85 @thedpt