I'm building a 16" M14 for myself in an attempt to make an accurate SOCOM 16. The rifle will be built on a Bula Forge receiver with mostly GI parts, a unitized gas cylinder, a Criterion 16" barrel and will be cut with an M852 Manson chamber reamer. I will start off with a Springfield Armory SOCOM 16 gas lock muzzle brake.

I will eventually switch out the muzzle brake to a Delta-P SOCOM adapter and add a SureFire Muzzle brake.

I will be experimenting with a GI fiberglass stock, a JAE chassis, SAGE chassis, Blackfeather chassis, an AG composites carbon fiber stock (bedded) and a bedded Big Red Birch stock.

Scope mount will be a Sadlak Airborne mount.

I have never loaded for the 308 in 16" before. All the loads I have are for 22" barrels.

I am asking for your pet loads for 16" specific barrels that are accurate and efficient. I don't want to burn excess powder that's not needed. I have the current powders on hand:

-8208 XBR
-IMR 3031
-Varget
-RL 15
-IMR 4064
-IMR 4895
-H4895
-W748
-H335

Available Bullets:
-125gr TNT's
-168gr Nosler CC
-175gr Nosler CC
-155gr Berger Hybrids
-168gr Berger Hybrids

The hard part about these rifles is that I don't think anyone knows a good load for them. Once I have a good load, then I can tune the rifle. I did manage to dial one down to 1.3" for a customer after a few range trips and a bedding job. He reported back that the rifle "exceeded his expectations."

Few have really tried to match condition these but I feel its something I need to learn.

Short range (<300yds) and medium range (<600yds) loads are appreciated.

Thanks for your assistance.

Tony.

I don’t know specifics about accuracy, which can be somewhat individual per firearm. I can see some load and function testing at 1st anyway.

For initial testing I would look at one of the 4895s ballpark for burn rate and 150-155 grain bullets. I find that H-4895 meters slightly better, at least through my powder measure. I use Ramshot TAC a fair amount too.

When just testing accuracy I often use a Sierra Matchking in whatever I’m loading for.

I have a new one on the way since Christmas, a rolling block in ‘8mm Label’. It once had a life in the French military(‘used little, dropped once’?) Just wanted to mention the oddball round, the Son has the interest.

IMR 4064 with the 168SMK is very much a standard load for the M-14/M1A, for the short to medium range.

In Service Rifle competition circles, I remember people shying away from heavy bullets because of the operating rod.

I think the bullets you listed are fine, except perhaps for the 125TNT which might be too light for the action to operate well.

W748 is not advisable in .308 with the 168-175 bullet weight. Other powders are good, but I would check at the Hodgdon website.

It shows that the highest velocity will be with IMR 4064 then IMR 4895 and then Varget. The fun thing is that Varget shows the lowest pressure and yet is still near the top in velocity. All this is in a 24 inch barrel.

Right. I understand all that but I wanted to approach this from a new angle. The SOCOM is a unique animal compared to the scout and full length cousins. Although it has the same mechanical function, the gas port is enlarged and traditional loads waste powder.

I was looking for popular loads guys use in their SCARs , 16” AR’s or shorty bolt guns that would be safe in mine.

Most SOCOMS are horribly over-gassed. I’m planning on using a Schuster gas plug and opening it wide open to stop the action from cycling, then tuning it with a good load to get it cycling from there.

I’m looking for good powder and bullet combinations that give me greater that 90% burn before the bullet leaves the barrel.

If I can hit 2500 with 175’s or Berger hybrids using Varget, 4065 or RL-15, that would be great.

I could cut the chamber with a reamer Bette suited for 175’s. I have one on hand. It’s sort of an Obermeyer type reamer.

Tony.

quote:

I’m looking for good powder and bullet combinations that give me greater that 90% burn before the bullet leaves the barrel.

You probably need Quickload for such minutae.

Me? I'd just load some Varget - although 4895, 4064, and Re15 did as well - and go shooting. But then I don't have anything longer than 28" or shorter than 20".

Given what you're trying to do in such as short barrel, I'd be inclined to start with the faster stuff on your list and go from there. 3031, 8208XBR, 4895, and so forth.

I'm curious about what you come up with for such a short barrel.

quote:

Originally posted by benny6:
Right. I understand all that but I wanted to approach this from a new angle. The SOCOM is a unique animal compared to the scout and full length cousins. Although it has the same mechanical function, the gas port is enlarged and traditional loads waste powder.

I was looking for popular loads guys use in their SCARs , 16” AR’s or shorty bolt guns that would be safe in mine.

Most SOCOMS are horribly over-gassed. I’m planning on using a Schuster gas plug and opening it wide open to stop the action from cycling, then tuning it with a good load to get it cycling from there.

I’m looking for good powder and bullet combinations that give me greater that 90% burn before the bullet leaves the barrel.

If I can hit 2500 with 175’s or Berger hybrids using Varget, 4065 or RL-15, that would be great.

I could cut the chamber with a reamer Bette suited for 175’s. I have one on hand. It’s sort of an Obermeyer type reamer.

Tony.

I am curious what you discover with the various stocks. I have a 2nd gen JAE for my full size with unitized gas system, Tubbs springs and sadlak I think recoil spring guide. Sadlak pistons etc. 43.5 grains of IMR 4895 and 167 match kings will do 1 or 1.2 MOA and that goes to 1.6 1.75 or so for the socom all stock except for the unitized gas system. I wanted a load for both. Agree socom over gassed have after market plug for mine seems to help. If you can find out what SCAR users have done would also be interesting. I suspect that you have forgotten more about m1as that’s I know, you have helped me out a couple times with questions I have had. Really interested in what you come up with have been considering a JAE stock for the socom and moving to a GG and G bipod for it like what i have on the full size don’t like the location of the stock GI bipod.

I had great success with XBR 8208 and 155gr projectiles. It was a great combo that was stable out to 700-800yds out of a 20" AI AE 308.

Andrew

I ran a series of tests with a Rem 600, 308 with a 16 inch barrel. Load was 168 Sierra, LC match brass, Fed match primer, 42.2 of 4895. Actual chrono muzzle velocity was 2419 average at 80 degree temp. Sighted in at 200 yards the impact was 3 inch high at 100, 11 inch low at 300 and 63 inch low at 500. I hit targets out to 750 using "best guess" method. Venue was Gunsite Academy
Hope this helps.

quote:

Originally posted by Sagamore-One:
I ran a series of tests with a Rem 600, 308 with a 16 inch barrel. Load was 168 Sierra, LC match brass, Fed match primer, 42.2 of 4895. Actual chrono muzzle velocity was 2419 average at 80 degree temp. Sighted in at 200 yards the impact was 3 inch high at 100, 11 inch low at 300 and 63 inch low at 500. I hit targets out to 750 using "best guess" method. Venue was Gunsite Academy
Hope this helps.

Interesting all match set up. Easier to get match primers now again. Do you have a source for the LC Match Brass? I have been using the Starline but Lapua does better, though right around a buck per. IMR 4895? I am assuming Boat tail as well.
Is Gunsite as good as advertised?

quote:

Originally posted by benny6:
Right. I understand all that but I wanted to approach this from a new angle. The SOCOM is a unique animal compared to the scout and full length cousins. Although it has the same mechanical function, the gas port is enlarged and traditional loads waste powder.

I was looking for popular loads guys use in their SCARs , 16” AR’s or shorty bolt guns that would be safe in mine.

Most SOCOMS are horribly over-gassed. I’m planning on using a Schuster gas plug and opening it wide open to stop the action from cycling, then tuning it with a good load to get it cycling from there.

I’m looking for good powder and bullet combinations that give me greater that 90% burn before the bullet leaves the barrel.

If I can hit 2500 with 175’s or Berger hybrids using Varget, 4065 or RL-15, that would be great.

I could cut the chamber with a reamer Bette suited for 175’s. I have one on hand. It’s sort of an Obermeyer type reamer.

Tony.

Why 175 grain? BC? Supersonic at 1000? I like the idea of using 4064 I have enough left to do a trial just with the socom. And have been looking for an excuse to get some VARGET. Come to think of it I have some 175 BT over some IMR 4895 that I could try. Have to look at my records for the charge weight.

Substituted Federal match brass when I ran out of LC match. Worked well.
My rifle does not like 175's as well as 168's.

On the subject of Gunsite Academy.... 4 visits....first 3 were fantastic - rifle , pistol, and shotgun all under the Colonel. Final visit not so much so. Advanced rifle with no Colonel. Received a full refund and declined an offer to be a staff rifle instructor.

quote:

Originally posted by Sagamore-One:
Substituted Federal match brass when I ran out of LC match. Worked well.
My rifle does not like 175's as well as 168's.

Is why I was asking about the 175s little heavy for M1As but used because can be supersonic at 1000. Too rarified for me. Federal Match I can fine and will likely dial in another grain or so for what I use with military brass or even the Starline.

The colonel one in a million it seems though I never met him.

You may want to rethink a 16 inch barreled 308 for 1000 yards as you will be shooting on the ballistic back curve where the bullet will be dropping at a severe rate. It is not unusual to see oblong bullet holes at these distances.

quote:

Originally posted by Sagamore-One:
You may want to rethink a 16 inch barreled 308 for 1000 yards as you will be shooting on the ballistic back curve where the bullet will be dropping at a severe rate. It is not unusual to see oblong bullet holes at these distances.

I am just curious what Tony Ben comes up with. I love his videos, have learned a lot from him. I am pretty satisfied with my m1as though the standard is likely to appreciate a new barrel soon. they both can shoot better than I can hold them except maybe prone with the bipod. 308 at best an 800 yard cartridge though the pros can do better. Not easy to find a 500 yard range much less anything longer. Anyway all of this is to talk myself into the 6.5 creedmore M1a. 308 mags work just fine. I am old enough have seen many caliber fads come and go and the eyes keep getting older and the limbs weaker maybe stay with 308 and experiment.

You're familiar with the website https://m14forum.com/forums.php I'm sure.
There should be m14 plumbers there willing to share info.

You're getting into a rather specific area here asking about cut-down M14 Platforms, imho.
Here's a pix of one of mine standard length m14s platforms to give this thread a little art:

quote:

Originally posted by drshame:
You're familiar with the website https://m14forum.com/forums.php I'm sure.
There should be m14 plumbers there willing to share info.

You're getting into a rather specific area here asking about cut-down M14 Platforms, imho.
Here's a pix of one of mine standard length m14s platforms to give this thread a little art:

What bipod is that? I went with one of the compact GG and G ones. Whatever shall I do with the old GI one?

Recycled stock Harris that's been great on every platform I had it on.
It's on a USGI Fiberglass M-14 stock that I did work on for my needs and refinished.
LRB Reciever, Smith Barrel/Trigger group, USGI Bolt. Nice shooter but a pricey project.

I came here to post about my LabRadar and just saw that this post came back to life. I tried some Black Hills 175 grain match out of my SOCOM in a JAE and I did get just over 2500 FPS at the muzzle.

JBM ballistics says that load will be 1123 FPS at 1,000 yards which is just 6 FPS over the speed of sound. So still supersonic at 1,000 yards.

I was also running a 155 grain Berger Hybrid under 42.5 grains of IMR-3031 in a Lake City case and was hitting an average of 2672 FPS at the muzzle. At 1,000 yards, JBM says that load will still be running at 1,145 FPS.

That same load out of a 22" barreled M14 was running 2785 FPS 10 feet from the muzzle (measured with a CED M2 on another trip) and will be running 1221 FPS at 1,000 yards. At 1,100 yards, the load is subsonic, so the max distance on that load out of a 22" barrel is still 1,000 yards.

So if I can tune this rifle, I can have a pretty decent mid-range rifle that will be perfectly capable of ringing steel inside 1,000 yards.

Accuracy with this thing is all over the place and it's going to be a long journey. I think the problem with the SOCOM is that the gas port is too close to the muzzle and that there's too much going on too close to where the bullet exits the muzzle.

I just got a Delta-P gas lock and used it yesterday with a Precision Armament M4-72 compensator and WOW! They should call this thing the TORNADO! I've used other brakes before with SOCOMs and they were more of a kick in the face. This was more like a strong breeze. A very powerful breeze, but not a painful kick.

Tony.