10.5" AR Issues?

[Dirty J]

Here's a good article on that topic. Covers muzzle velocity and pressure at the muzzle.

http://www.sadefensejournal.com/wp/?p=1093

 

[Lazarus]

You shouldn't have any problems with that length as long as everything else is like it should be. I ordered a 10.5 Seekins upper and was having problems cycling, come to find out the gas block wasn't lined up with the gas port. Once that got squared away its been mint ever since.

I'm an expert by no means, but ive always been told that 10.5 is as short as you want to go with a 556 upper. That's the shortest length you can keep a carbine length gas system.

Both Colt and Daniel Defense use 10.3" barrels in their MK18 uppers.

 

[KingTuna]

Hey, i was pretty close. I was only off 2/10ths of an inch.

 

[NewLeaf]

did you chrono for velocity?

not intending sarcasm - just looking for velocity measurements.

No Sir, I do not.

 

[RiverBend]

I'm running a 7 1/2, (mostly a novelty) and never had issues, as long as your upper has the double M4 feed ramps it should run fine.

 

[sovietak474u]

Agreed, I kept messing with the gas system over&over. Bought a CMMG "enhanced" pistol buffer & spring.....problem solved. And sorry, but I don't get the 10" and up rule?? With Much Respect.... we've put 7.5 up against 10.5 with no Real difference except my 7.5" fits in my favorite bag

When someone is having issue with function and it has a 10.5 inch barrel or lower 99% of the time it is a gas problem. Buffer usually follows right behind it. Just a basic checklist to trouble shooting a problem

 

[Spiderman11]

Your 10.5 PSA will be just fine . . . About 2,000 rds through this one . . . Upper and lower are straight out of the box - no mods -(minus suppressor attachment). Never had an issue, suppressed or unsuppresed - brass, steel, 55gr, 62gr.