Saint pistol. Why so short a barrel.

[Kevslatvin]

Just looked at the specs on the Springfield Armory Saint Pistol. 7.5" barrel. Why so short? Is the maneuverability worth the trade off in lost velocity. I thought under 10" velocity really suffers as do your ears. Just curious.

[Diamondback]

Could it be the 26" line between "Pistol" and "Other Title I Firearm" in the ATF classification system? ("Other T-I" is the same class as TAC-14 and Mossberg Shockwave, "Title II" is all the NFA Registered classes.)

Admitted, 7.5 is a bit on the low end... without a muzzle device and using a regular CAR-length buffer tube you can go all the way to 11" and still be in Federal "pistol" class. Maybe they did it for CQB or BOB/GHB/Truck & Trunk Gun carry... IIRC most flashcans are only about 2-3" and that woulda still left another inch or two for barrel.

[Kevslatvin]

Could it be the 26" line between "Pistol" and "Other Title I Firearm" in the ATF classification system? ("Other T-I" is the same class as TAC-14 and Mossberg Shockwave, "Title II" is all the NFA Registered classes.)



Maybe. I'm not very knowledgeable on that stuff. Now I'm confused. If I built a pistol and it is longer than 26" OAL is it no longer a pistol and is there trouble I can get in for it?

[Diamondback]

Maybe. I'm not very knowledgeable on that stuff. Now I'm confused. If I built a pistol and it is longer than 26" OAL is it no longer a pistol and is there trouble I can get in for it?
Depends on what your State laws say. Under Federal law, an over 26" "megapistol" is in the same class (unrestricted, non-NFA) as a Remington 870 TAC-14 or a Mossberg 590 Shockwave, but you can also put a vertical foregrip on it where a pistol getting one below that length would become an NFA AOW.

For example, here in Washington, a "pistol" is defined as "16" or less barrel, no stock, designed to be fired with one hand"--so depending on the flash-hider length I could take the upper of a 14.5" milspec M4 (which on a rifle lower would be a Title II SBR), slap a pistol lower under it and if I can conceal it (not bloody likely with my build admittedly), I can legally carry it loaded, while Michigan says anything over 26" is not covered by a CPL and has to be unloaded while in a vehicle. It's not just what you can own, but what you can legally carry with ammo loaded up and ready to go, and every state's different... I don't know what Tennessee says about carrying AR-pistols.

[Kevslatvin]

Interesting. Looks like I have some homework to do before any future pistol build. I don't know the rules on carrying an AR pistol with a carry permit, but I do know the law recently changed( a year ago I think) and now lets you have a loaded handgun, shotgun or rifle in your vehicle with or without a carry permit. Previously it was only handguns with a valid HCP.

[heavygunner8]

is a 7.5" AR even viable at all? The conventional wisdom is to never go below 10.5

[bad aim]

I agree with the above, wasn't that the reason why .300 became popular, the ability to go <10.3" and still have a reliable platform?

[Leaveammoforme]

Is a 7.5" AR even viable at all?The conventional wisdom is to never go below 10.5

Yep. I've chrono'd 855 that was close to 2400 fps before. I recently loaded up some 50 grainers and have pushed them to almost 2500. Next stop....breaking 3000 fps with 35 grain projectiles.

[heavygunner8]

Yep. I've chrono'd 855 that was close to 2400 fps before. I recently loaded up some 50 grainers and have pushed them to almost 2500. Next stop....breaking 3000 fps with 35 grain projectiles.

How’s the reliability?

[Leaveammoforme]

How’s the reliability?

Only issue I've ever had was FTFeed with light projectiles moving around 2000 FPS (which is low end .223 loads). Those same loads wouldn't reliably cycle an 11.5 either though.

Granted my 7.5" is a piston gun, so it's not really an "apples to apples" comparison with the Springfield offering. DI guns can be a little more finicky.

[Shiz]

Their logic escaped me on this one. 11.5 all day. What would have really been cool is a 12.5. 7.5 even too short for a silencer.

[Leaveammoforme]

Their logic escaped me on this one. 11.5 all day. What would have really been cool is a 12.5. 7.5 even too short for a silencer.

Nah.

Suppressors exist for the super shorties but choices are narrowed down. The Sandman's come to mind. But, I do believe suppressing 5.56 in the 7.5" range to be kind of a waste.

The whole point, in my mind, of a 7.5" is for the compactness. The compactness is lost when a suppressor, or even a long muzzle device, is installed. A suppressor or a long muzzle device may take the bite out of the muzzle blast but so will a longer barrel.

[Spiffums]

Depends on what your State laws say. Under Federal law, an over 26" "megapistol" is in the same class (unrestricted, non-NFA) as a Remington 870 TAC-14 or a Mossberg 590 Shockwave, but you can also put a vertical foregrip on it where a pistol getting one below that length would become an NFA AOW.

For example, here in Washington, a "pistol" is defined as "16" or less barrel, no stock, designed to be fired with one hand"--so depending on the flash-hider length I could take the upper of a 14.5" milspec M4 (which on a rifle lower would be a Title II SBR), slap a pistol lower under it and if I can conceal it (not bloody likely with my build admittedly), I can legally carry it loaded, while Michigan says anything over 26" is not covered by a CPL and has to be unloaded while in a vehicle. It's not just what you can own, but what you can legally carry with ammo loaded up and ready to go, and every state's different... I don't know what Tennessee says about carrying AR-pistols.

Our carry permits cover them.

[Jeepman1320]

I don't think the use of a K can on a 7.5" 5.56 is a waste. You still have a very compact platform and a K can will take more bite out of the muzzle blast than simply running an 11.5" barrel. The Sandman K doesn't have a minimum barrel length, but I would still run their muzzle brake as a sacrificial baffle if you did run one. I wouldn't plan on shooting a super short barreled 5.56 without a suppressor if you had one available. The 7.5" barreled 5.56 are simply not fun to be around because of the concussion in my opinion. Personally below a 10.5" I would probably lean towards a 300blk over the 5.56.