12.5 308 Aero?

[KCode]

Finishing up my 16 inch 308 build ans I already want a 12.5 for fun. From what I can see it would still send a 30cal projectile weighing 135gr around 2500fps. Would also probably do ok with subs.

What say you for SHTF type all purpose inside 200 yards?

 

[hlee]

I have a 16” 308 that I really like. But, I also have a 12” 6.5 Grendel that is pretty awesome. I think the weight/size savings of a small frame Grendel outweighs the potential performance gains of a 12” 308win- inside of 200 yards…

 

[KCode]

I have a 16” 308 that I really like. But, I also have a 12” 6.5 Grendel that is pretty awesome. I think the weight/size savings of a small frame Grendel outweighs the potential performance gains of a 12” 308win- inside of 200 yards…

The older I get the more I want to simplify my reloading. I thought about Grendel but decided to stick to 30cal and .223

 

[Cascade Hemi]

Finishing up my 16 inch 308 build ans I already want a 12.5 for fun. From what I can see it would still send a 30cal projectile weighing 135gr around 2500fps. Would also probably do ok with subs.

What say you for SHTF type all purpose inside 200 yards?

I'm loading 155gr and they go 2400fps. 135gr should get close to 2500 but I have not actually tried it myself.

Here is a post I made about a 12.5" 308 Win: https://www.snipershide.com/shootin...ild-info-picture-thread.6252642/post-11774240

Honestly, it's a toy. Even with a silencer it is super loud. Without a silencer you'll probably get hearing damage without doubling up hearing protection. With that said, there is no doubt a 12.5" 308 is lethal inside 200 yards.

 

[LRRPF52]

If you shoot 125gr from the 12.5” .308, you’ll be doing 2700fps pretty easily. 125gr .308 bullets have really low BCs, but they are great for fast kills within 300yds. You have 125gr SST, 125gr TGK, 125gr TMK, 125gr Nosler BT, and 125gr Nosler Accubond options too.

135gr should do 2610fps.

147gr 2512fps

155gr 2450fps

 

[KCode]

So it really sounds like a 12.5 308 isn't THAT big of a dumb idea.

Only downside I can see is it would be loud. Also how hard would it be on a suppressor?

 

[Overwatch260]

So it really sounds like a 12.5 308 isn't THAT big of a dumb idea.

Only downside I can see is it would be loud. Also how hard would it be on a suppressor?

I'm building a 13" 308 & been looking at suppressors for it... A few companies I've seen recommend for SBRs to run a HUB mount with a muzzle brake as a sort of "sacrificial baffle" so it isn't as hard on the actual blast baffle of the can itself. Makes sense to me so that's the way I'm planning to go.

 

[Cascade Hemi]

So it really sounds like a 12.5 308 isn't THAT big of a dumb idea.

Only downside I can see is it would be loud. Also how hard would it be on a suppressor?

50:50 mix of rad and dumb. Don't go shorter than MLGS. It's pretty handy compared to full size AR10s. It was a fun project.

The Recce7 handles it fine. The fireball without the can is 3' long.

 

[KCode]

50:50 mix of rad and dumb. Don't go shorter than MLGS. It's pretty handy compared to full size AR10s. It was a fun project.

The Recce7 handles it fine. The fireball without the can is 3' long.

MLGS?

Edit: Medium length gas system. That took a minute

 

[thedude824]

I’ve got a 13” SCAR 17. Fired it once without a can with double ear pro. There was nothing fun about it. Given I’ve done a few search warrants it’s definitely not what I would want. IMO it needs a can. If you are DI you’ll not only need a can rated for a short barrel, but the action will foul pretty quickly… unless you use a flow through can. IMO the only time a SBR 308 makes sense FOR ME is piston driven and flow through can. I use the HUXWRX Flow 762. I train with 147 grain handloads, but have stockpiles of handloads with 125 Controlled Chaos I bought on clearance and loads of 125 SST. I actually use that rifle on run and gun rifle nights. With the DiSCARder, HUXWRX, and Geissele trigger it’s really not much more cumbersome than the 556 rifles, but with superior ballistics… and no concerns or stoppages from fouling. It’s really an impressive system IMO. That’s my story

 

[Cascade Hemi]

If you are DI you’ll not only need a can rated for a short barrel, but the action will foul pretty quickly… unless you use a flow through can.

There is no practical difference between a 16" MLGS 308 Win and a 12.5" MLGS 308 Win with regards to operating system fouling. My experience actually says the lower dwell is easier on the operating system and stays locked longer.

As far as Di vs Piston with silencers. DI is simply more forgiving which is why flow through makes more sense with a large frame piston gun. It's been years but I've built SBR FAL's and they never really worked right transitioning between suppressed and unsupressed without custom drilled gas plugs and static ammunition selection. If OP were building a FAL or SCAR you'd be right on the money but with an AR10 you really just need an adjustable gas block or gas block drilled to size (.063 to .070 depending on silencer selection).

 

[Dogtown]

My favorite shorty .308...