Best SBR load?

[ruggedtraditions]

Anyone got some good data on optimized loads for a 10.5-12.5" barrels, chambered in 5.56mm?

I have been searching but havent found much.

Will a faster burning powder = higher velocities, or is this just a myth?

I am considering getting a noveske barrel. I have heard rumors of the polygonal rifling having higher velocities. Can anyone confirm this?


I have never loaded for any shorter barrels before, and im wondering how much you can optimize for velocity and complete powder burn.

Or are LOUD Fireballs just part of the bargain.

Thanks for your help.

 

[ruggedtraditions]

Bump

 

[snuffy]

I guess it would help if we knew what a SBR was?!

 

[zoomie]

Short Barrel Rifle, snuffy; rifle with barrel <16".

 

[snuffy]

I hate acronyms, but that one is an oxymoron. Or another way to say it a misnomer. To dumb it down further, it is miss named. Something that short is a pistol!:barf: Balls O' fire would be the result with any powder, along with muzzle blast. Good luck,(and don't let the feds find you!)

 

[Hkmp5sd]

Something that short is a pistol!

Not according to the Bureau of Alcohol, Tobacco and Firearms. It is a firearm that is so dangerous it requires a FBI background check and a $200 tax before you can own one.

 

[ruggedtraditions]

Wow. Apparently this was the wrong forum to ask at.

Short Barreled Rifles-SBR can legally owned by civilians, if they will out a form 1 and create a registered firearm under the National Firearms Act of 1934.

A pistol does not have a stock a rifle does, even if it is a "pistol" length barrel.

I was hoping for some helpful info, from people with experience.

 

[Hkmp5sd]

I was hoping for some helpful info, from people with experience.

Most of us know what a SBR is along with SBS, AOW and NFA. I've been through the process 6 times myself, including a Colt M16A1 with a 14.5" barrel (machinegun, not SBR).

Unfortunately, few people reload the 5.56 in an attempt to optimize it for the shorter barrel. You already get a really loud and big fireball with that barrel length, so the only thing to do is start dropping the powder load. Or do like I did and buy a .223 suppressor.

 

[ruggedtraditions]

It will be suppressed for sure.

I am just wondering if its possible to squeeze out some extra velocity from a short barrel.

I am planning on loading heavy bullets 70-77gr to compinsate for lower velocities. I have found lots of info on MK262 ammo, but nobody seems to talk about optimized loads for the short barrels.

I have found some info on the new "brown" tip ammo, but no discusions on the powders used.

 

[snuffy]

Wow. Apparently this was the wrong forum to ask at.

Short Barreled Rifles-SBR can legally owned by civilians, if they will out a form 1 and create a registered firearm under the National Firearms Act of 1934.

A pistol does not have a stock a rifle does, even if it is a "pistol" length barrel.

I was hoping for some helpful info, from people with experience.

Not trying to criticize, I just want to stay under the radar.

1. I know short barreled rifles can be owned by us unwashed masses. I just don't want a target on my door, be subject to a search whenever the BATFE feels like it, and have to wire my house for security.

2. I don't want a short barrel rifle. Short barrel and rifle don't go together.

3. The only experience I can give you is, I own a "normal" length,(20") AR, AND a super 16 contender in .223. I haven't done much loading for the contender, the AR is much more fun to shoot and MUCH quieter.

 

[ruggedtraditions]

If your not trying to criticize, and you want to stay under the radar, then why even bother posting a reply to a question about NFA items.

Leave the replies to people with helpful info.

 

[darkgael]

SBR

I read once, in a reloading manual, that, counterintuitively, the best powders/loads for a cartridge in a rifle are often the best loads for it in a pistol. I know that there is some disagreement about that also. They were talking about loads for the Thompson Contender which is similar territory to your SBR. I have a short .223 barrel for my Encore. I don't do anything different other than restrict my bullets to 55 grains and lighter.
Pete

 

[bustoff]

I also have a encore in 223. I also shoot 50,52 and 55 gr bullets. H322 has given me good results and yes it is loud. check the single shot pistol section in the load books for 223 loads, it may be a good place to start. the encore has a 15'' barrel

 

[zxcvbob]

You'll get the highest velocity using the same powder that you do with a long barrel -- but you'll get a lot more muzzle blast with the slow powders and short barrel. A faster powder will reduce the blast without necessarily reducing the muzzle velocity very much (and you can use less powder.)

 

[Hkmp5sd]

be subject to a search whenever the BATFE feels like it, and have to wire my house for security.

Perpetuating urban legends.

I've owned NFA items for over 20 years. I've maintained a C&R (03) FFL for over 20 years. Formerly had a dealer (01) FFL operating out of a home. Never seen an ATF agent in my life.

 

[NWPilgrim]

From what I have read you want faster powders that will burn more completely before exiting a short barrel.

In the case of .223 with a 77gr bullet that would be more like H335 or H4895. I understand what you are working on but the factors are kind of working at cross purposes in terms of powder speed and so you end up with a compromise or average burn rate.

The heavy bullet would normally favor a slower powder like Varget, IMR 4064, Re15 (well slower in the .223 at least). But a short barrel favors a faster powder like H322. So for a combination of short barrel and heavy bullet you are likely to find the best powder (good velocity yet less flass, relatively speaking) to lie in the fast side of average: Benchmark, H335, H4895.

Play around with different combinations and see what you like: H322 with 55 gr bullets, and H335 or H4895 with 77 gr bullets.

 

[rawiron1]

I have a 10 1/2" AR. I tried using T/C data and the hottest load I could find for a 50gr. bullet would not cycle the action in my AR. I used 20" AR data for a mid-range 50gr. load and it ran fine. Shoots 1.5" at 100 yards. NO muzzle flash even in low light. Although you will see a spark now and then come out of the flash suppressor. Mil spec loads on the other hand will shoot fire out of this gun even at high noon on a sunny day. I currently run IMR-4198 in my loads.

I have a low light vid of this gun being run but when I posted it someone got SBR envy and gave me a line so I won't post it again. You'll just have to take my word for it.

Rock River SBR AR-15
Glock-19 with YHM suppressor
Serbu Super Short AOW

Some other notables in the collection...

Enfield No. 4 MK-II, unissued, unfired
SOCOM-16

I'll stop here before I get lined again. lol

 

[darkgael]

About using those 77 grain bullets (Sierra MatchKings ?)...you are going to need a 1-7"/1-8" twist for your rifling. Is that your plan?
Also.... Running your SBR... While I cannot doubt someone's real experience.....a little checking shows me that load data for .223 in the AR and the T/C Contender is pretty much the same.

 

[jmorris]

I run my 10.5" AR with the same loads I use for all the rest of them and the contender for that matter.

If I want more power, I just grab something else.