Reloading for an AR15 - SBR

[AzDak42]

I'm happy to say that I'm about a week away from my SBR paperwork coming through and I'll be able to pickup my custom lower! I have a 10.5" LMT sitting with a vendor waiting for my paperwork before they ship it to me.

So... I know this is a bit out of the realm of the normal load discussions on this forum, but how about some good loads or even discussion around what hand loads would make sense?

Right now I'm thinking I might go one of two ways. One option would be to try and find a 75g load similar to the TAP home defense load or try a load with monolithic bullets in the 60g range.

Evidently the LMT 10.5" uppers have a very small gas port, so you need to run full power to get it to cycle.

Thoughts?

 

[Huntbear]

Just curious.. I am not always the quickest to catch on to abbreviations..

What does SBR stand for?

 

[AzDak42]

Short barreled rifle. It's the process of procuring a $200 tax stamp through the ATF that allows you to own rifles with less than a 16" barrel. You get to spend money, get some passport photos, fill out paperwork, get finger printed, sit through approval of your local LEO and then... wait 6 months for the ATF to send back the approved paperwork.

A lot of local LEOs in some states won't sign off, and some states prohibit them. But living in AZ, it's fair game. (As are suppressors if you want to go through the same hi jinx)

 

[Huntbear]

Oh, I know all about the tax stamp and the atf... lol.

Just that abbreviation threw me....

Thank you

 

[Wincheringen]

Are you going to be running a can on it also? I had an 11.5" 5.56 but I didn't load for it. Velocity for most 55 grain loads was right around 2600 FPS so it didn't give up much with the shorter barrel.

 

[300WSM]

I load a lot for the AR platform....but first thing
What are your expectations? A 10.5 inch bbl has its limitations regardless the load and bullet combo
and rate of twist. You can have perfect bullet weight for the twist and such but you will hit the ceiling pretty quickly on the stabilization.

I would suggest taking a look at the IMR XBR powder...it has always performed well....especially in shorter bbl length AR's ...like the 14 and 11 inch with long supressor's...XBR does as well as anything I've tried in the AR short BBL's

 

[AzDak42]

Are you going to be running a can on it also? I had an 11.5" 5.56 but I didn't load for it. Velocity for most 55 grain loads was right around 2600 FPS so it didn't give up much with the shorter barrel.

Eventually. It's in the toy queue for sometime next year depending on how a few other projects work out. I'd really like to have one for my AR10, so it's kind of a bugger to figure out which one goes first.

What are your expectations? A 10.5 inch bbl has its limitations regardless the load and bullet combo
and rate of twist. You can have perfect bullet weight for the twist and such but you will hit the ceiling pretty quickly on the stabilization.

I would suggest taking a look at the IMR XBR powder...it has always performed well....especially in shorter bbl length AR's ...like the 14 and 11 inch with long supressor's...XBR does as well as anything I've tried in the AR short BBL's

My expectation is to have some fun with an AR and play around with some loads.

I think more than anything, I'd like to eventually come up with one load that will 'do it all' well enough. The 5.56/.223 is the round that will eventually push me to get a Dillon press to speed things up. (I shoot a lot of .223...)

That's kind of a ridiculously tall order though... As I want it to work in a 20" A4 (1:9), 16" M4 (1:7), 18" SDM (1:7) and now a 10.5" SBR (1:7).. (Sort of like asking for a magic pony... )

Right now I'm leaning toward the 69g Sierra. It shoots sub-moa out of my SDM and still shoots well out of the 20" & 16" guns.

 

[300WSM]

My expectation is to have some fun with an AR and play around with some loads.

I think more than anything, I'd like to eventually come up with one load that will 'do it all' well enough. The 5.56/.223 is the round that will eventually push me to get a Dillon press to speed things up. (I shoot a lot of .223...)

That's kind of a ridiculously tall order though... As I want it to work in a 20" A4 (1:9), 16" M4 (1:7), 18" SDM (1:7) and now a 10.5" SBR (1:7).. (Sort of like asking for a magic pony... )

Right now I'm leaning toward the 69g Sierra. It shoots sub-moa out of my SDM and still shoots well out of the 20" & 16" guns.

You are on the right track with the 69gr. One bullet won't work perfect in them all because of the different lengths and twist rates, but 60-69 gr bullets are the answer to your hope of getting as close to working good in all of them as possible.

 

[Wincheringen]

Easy enough to just get a .308 can and use it on both. Thats what I do. Nobody makes a hearing safe .223 can so the minute difference in performance isn't going to matter. The newer titanium cans are very light so the larger .308 can won't even be noticed.