.300 Blackout build!

[Heytrap]

I recently built my 300 Blackout. It is very accurate with jacketed 110 & 125 gr bullets at 100 yds. I have grouped 5 rounds that could be covered up by a quarter. I think you will be happy with performance. The question that I have would be using it with cast boolit. I only have one 30 cal mould. It is 311291. I tested 5 rounds a few weeks ago and couldn't get it to feed up the ramps properly plus didn't want to cycle either. So, I been looking for a mould that would work. I found a RCBS 7.62 x 130gr SPL. I was wondering if anybody has tried this boolit? I would buy a mould no problem but would like to try a few boolits out first.

[sparky45]

I to had problems with the 311291, similar to yours. I just received another mold today and will cast either tonight or tomorrow and let you know how it goes. The new mold(new to me) is Lyman 311414 150gr.

[RU shooter]

I recently built my 300 Blackout. It is very accurate with jacketed 110 & 125 gr bullets at 100 yds. I have grouped 5 rounds that could be covered up by a quarter. I think you will be happy with performance. The question that I have would be using it with cast boolit. I only have one 30 cal mould. It is 311291. I tested 5 rounds a few weeks ago and couldn't get it to feed up the ramps properly plus didn't want to cycle either. So, I been looking for a mould that would work. I found a RCBS 7.62 x 130gr SPL. I was wondering if anybody has tried this boolit? I would buy a mould no problem but would like to try a few boolits out first.

Another that should work quite well is the Lee 312-155(SKS) bullet

[badge176]

So I recently got the last part (gas tube) about the same time we got about 4 inches of rain over the week end. Well, the basement sump pump worked well but a PVC fitting (some goofy rubber fixture in-line - backflow preventer?!) blew its self loose so the pump vented INSIDE my basement! nice soggy mess! I hope to get to the assembly this Wed and Thu...

[Idaho Sharpshooter]

The 300 BLK has ONE insurmountable, and ONE really neat advantage: it uses standard (read $10-12 AR-15/M-16) magazines, not special (read expensive) ones. Really neat is that you make the cases out of 223 brass, and I bought 4000 from The Captain for 3.5 cents apiece.

Get an adjustable gas block, mine is a JP Enterprises one, and run anything from 125gr to 220gr jacketed, and 124gr all the way up to the awesome 311247 in it, suppressed or not, just tune the gas block to suit.

Rich

[mstarling]

I took a deer last fall with a suppressed 16" 300 BLK. 1:8 tube was made by Paladin Machine Services from Douglas stock and has his pistol position 3 way gas block. Runs subs in one position and supers in the other. Rifle was built on a Black Rain Ordnance upper/lower pair. Has a rifle length YHM light rail, a SOPMOD stock, and a Bill Springfield 3# trigger.

Deer fell to a 220 gr SMK at 1050 fps driven by 8,4 gr of 2400. Neck shot. DRT Projectile exited sideways.

The rifle is amazingly quiet with an SAS Ti Arbiter 30 cal suppressor but one should not shoot boolits through a sealed can.

Rifle does stabilize the 311247s just fine. Have not run them suppressed yet as the 5/8x24 fixed adapter for the user serviceable Octane 9HD can just arrived. Should be a hoot to shoot!

[RugerFan]

.... one should not shoot boolits through a sealed can.

Why not?

[Moonie]

Why not?

You can't clean the crud out. Lube and lead particles will accumulate inside of a can. If the can is sealed you can't easily clean them out. This is the theory.

[sheepdog]

the .300 Blackout is a medium...errr...a vehicle to boost suppressor and/or AR parts sales, in my opinion

You can't push a 240 grain out of an AK nor keep it silent. but you can also put full power loads in it if need be. I think really the draw is you can used manly 30 cal boolits with a can and still get 30 rounds per mag out of it. Thats a tough shoe to fill.

[RugerFan]

You can't clean the crud out. Lube and lead particles will accumulate inside of a can. If the can is sealed you can't easily clean them out. This is the theory.

Ok I gotcha. I Plan on getting one you can disassemble. Most likely from here....
http://coastalgun.com/

[xacex]

Another that should work quite well is the Lee 312-155(SKS) bullet

I have been working-up a load with this boolit myself. It seems to like the top end near 18g of h110. Over 18 and it will pop out primers. So far the best groups are at 17.6g with this rifle. I have weighed some of these boolits to the 10th of a grain, along with the powder charge to get a 4 shot clover leaf at 50 yards. I always get a flier on the 5th. By the end of summer I should have this rifle/boolit combo worked out.
I did have to modify the p-mags for the olgive on this one, and the longer 112- 185g.

[Russel Nash]

You can't push a 240 grain out of an AK nor keep it silent. but you can also put full power loads in it if need be. I think really the draw is you can used manly 30 cal boolits with a can and still get 30 rounds per mag out of it. Thats a tough shoe to fill.

Savage Arms basically said they could NOT get the heavy bullets to be accurate enough in their Model 10:

http://www.savagearms.com/

[Hamish]

OP still has not posted pics. Bad dog. Bad.

[mpbarry1]

So do you guys think this is a flash in the pan or a new caliber for the ages? It looks like a good cast bullet round to me. Mildly interested in it but i am pretty causious w new rounds.

[HodakaGA]

So do you guys think this is a flash in the pan or a new caliber for the ages? It looks like a good cast bullet round to me. Mildly interested in it but i am pretty causious w new rounds.

Doesn't matter one way or the other to me. It seems to fit what I'm looking for, a 30-30 or 7.62x39 power level round that functions in an AR-type rifle, easy to make brass, especially cheap to load using cast boolits.

I finally have all my parts on the way to finish my build. They should all be here this week!

I still have an order in line for a DSA stainless upper from 2/14/12. Not sure yet if I'll cancel the order or just hold on to it, if they ever decide to ship anything.

[Moonie]

So do you guys think this is a flash in the pan or a new caliber for the ages? It looks like a good cast bullet round to me. Mildly interested in it but i am pretty causious w new rounds.

I look at it this way, I have dies and molds. I can make brass from .223/5.56, it can't really be orphaned for me. I like it and shoot it alot.

[paul h]

So do you guys think this is a flash in the pan or a new caliber for the ages? It looks like a good cast bullet round to me. Mildly interested in it but i am pretty causious w new rounds.

If you reload, then it really doesn't matter as brass can easily be formed via .223 cases which will always be plentiful, and 30 cal jacketed bullets are also always going to be easy to come by.

I've been bitten several times by obscure cartridges, 350 rigby and 500 Jeffrey, as well as a factory round that never really caught on, the .480 ruger. The 350 and 500 were real pains due to the availaibility and cost of brass. The 480 has never been an issue as I have several molds and brass isn't that hard to come by. If worse came to worse I could make it out of 475 linebaugh brass.

Even if the 300 blackout fades in the future, you simply aren't going to have issues of components or spare magazines.

[Artful]

Savage Arms basically said they could NOT get the heavy bullets to be accurate enough in their Model 10:

http://www.savagearms.com/

My understanding was they tried to use their 1:10 twist barrels for heavy bullet subsonic ammo - not a good combination. You'd think they would be smarter - all the info is out on the "NET"

[Russel Nash]

they said at their webpage, IIRC, they tried various twist rates.

shrugs shoulders.

[L1A1Rocker]

My understanding was they tried to use their 1:10 twist barrels for heavy bullet subsonic ammo - not a good combination. You'd think they would be smarter - all the info is out on the "NET"

They were also running factory ammo designed to be sub-sonic from a 16 inch barrel in 20 inch barrels. Nobody is going to get decent accuracy from a bullet going trans-sonic speeds no matter what twist they use.

I don't get it, many people are getting great accuracy from this round in both sub-sonic and super-sonic loadings. Heck, some people have built some real tack drivers form SAVAGE actions. If Savage couldn't get good accuracy then someone wasn't really trying, didn't want it to work, or is too ignorant to be doing that job.