AR pistol, 7.5 vs 10.5?

[odmichael]

What do you guys recommend? Do the extra inches matter?

This'll be my first and I want to make sure I've got some info before I dive into this project.

Thanks

[Ride4frnt]

If I had to guess, you're going to get a general consensus of 11.5". Plenty of people have 10.5" but the reliability of 11.5 is much higher.

[GOST]

To me 7.5" is short for 2 reasons. 1 is that you won't have much real estate on the handguard for grip, you'll be all scrunched up. 2 is that it's gonna be very loud for the shooter. I agree with Ride on the 11.5" or maybe even a 12.5". For 5.56 I wouldn't go shorter than 10.3", but if your wanting to go really short you may want to try a 8.2" 300 BO.

[JoshAston]

I'm gonna go against the grain and say 7.5" because it's fun. They don't have much practical use, but they'll put a grin on your face!

[MonkeyBomb]

I have a 7.5. It's loud as hell. I mean concussively loud to anyone around you. Still Fun. I wished I would have gone 10.5 at least. anything under 10.5 will give you a good chance of blowing up an expensive suppressor and cause you to start all that paperwork again.

[VIPER 237]

Dwell time is stupid short on the 7.5 and they are finicky with different ammo, parts take much more abuse, its louder than hell and even though some suppressors can handle that short of barrel they are not hearing safe, ballistics are pitiful, and unless youre 5'5" the hand guard is too short.

10.3/5 is the shortest i'll ever go with the 5.56, but 11.5 is the sweet spot for me, I cant remember the exact spec but I think the extra inch from 10.5-11.5 give you close to 30% increase in dwell time.

[voodoo_man]

both?

[WHSmithIV]

I decided 10.5" for the 7.62x39 pistol I'm building. The main reason for that is because at 7.5" I'd have a serious flame thrower. It may still end up being a flame thrower, but not as much of one.

[AR-10]

I had a 7.5" upper on my pistol and it was SEVERELY overgassed.

I got rid of it and bought a DD MK18 upper.

[toolboxluis00200]

i have a 10.5 SBR and that is very very light easy to shoot and after i added a spike tactical Krink very controllable

http://youtu.be/-qrhS67-jgg?list=UUY...fA6WMUHATPaXJg

[Pyzik]

If I had to guess, you're going to get a general consensus of 11.5". Plenty of people have 10.5" but the reliability of 11.5 is much higher.

This. I went through what your're going through now.
10.5" was decided as short as I would go. I'd go 11.5 if I could get away with it. But funky laws here in MI are keeping me at 10.5 due to OAL issues.

[Uffdaphil]

OP doesn't specify caliber. Huge difference between 5.56 and 30 cal (7.62 & 300BLK). Larger bore allows shorter efficient length. 8.5 & 9" are standard short barrel Blackout lengths. I can't see 7.5" being radically different in performance in the larger calibers.

I have a 7.5" 5.56 pistol that has not given me problems (linear comp a must IMO), but I still wouldn't trust it as a primary defense weapon unlike my longer pistols.

[Kopis]

Do the extra inches matter?

Yes, why yes they do... just ask any lady!

I'm gonna go against the grain and say 7.5" because it's fun. They don't have much practical use, but they'll put a grin on your face!

That being said, what's your purpose for this gun? If it's just a fun gun, definitely go 7.5"!!! KX3 flaming pig comp does take some of the crack out but any pistol will be loud. I did the 7.5" because i wanted a compact PDW without a tax stamp. I can carry a lot of firepower in a small package.... and it's just a freaking blast to shoot. Everyone loves it.


I keep hearing about reliability issues with AR pistols but my two shooting buddies and I each have built a 7.5". all three different brands and we've all run lots of different ammo through them and never ever had a hiccup of any kind so i dont know if that's an older issue or what. I know the first AR pistol barrels had the same size gas port as a rifle which was causing dwell issues but most new pistols are utilizing a larger diameter gas port which has alleviated those reliability concerns to my knowledge.

I highly recommend the 3.5" extended buffer tube and sig brace. Really helps with the length of pull. Law Tac folding attachment point added another inch. Perfect now.

[UWone77]

Never owned anything shorter than 8.2" (300 BLK). The 7.5" I've shot needed to be tuned for the most part.

However, I decided to try out the 7.5" from Aero.

[GHOSTMAN]

Nice ar pistol