Gunsmithing SBR build questions

[jasonZ]

I'm wanting to build an SBR and I have a couple quick questions before I start shopping!

1st, should I look at a barrel/matching bolt setup? The build will be in 223 and I'm going to use my existing rifle which is chambered in 223, but with a 16" barrel. I know when I did my grendel build I bought a matching setup from sabre and I reckon that I should do the same this time, but I'm limited in AR build experience!

2nd, what else should I look at for this build? I'm only thinking of what I'll need to do an SBR barrel change. I know I have to get my stamp, but anything else? I'm figuring that since its already a complete rifle, I should be alright. I'm also planning on getting a new free float rail setup, so barrel nut should be covered too.

3rd, should I simply build a new upper instead? I would/could then build a new lower for a complete other rifle, since the lower would then be dedicated to the short upper from what I understand from reading about the stamp and such. Any other advice would be appreciated as well.
Thanks, Jason

 

[jasonZ]

Re: SBR build questions

Maybe I should've put this in the semi auto section? Nobody has any input on it?

 

[OnyxSkyDV]

Re: SBR build questions

Probably better in the semi-auto section, but I would think the BCG should be able to stay just fine. You will need the short barrel and matching gas system / block on it. If you want to use both then a second upper would be easier to do, and just swap the BCG between the two if you are trying to save some money.

Biggest issue I have heard of is holding the barrel and upper receiver straight so you can tighten on the barrel nut without throwing the gas tube alignment off. Have not done it myself yet, so can't speak to the difficulty.

hope that little bit is of some help.

Onyx

 

[killerwaffles]

Re: SBR build questions

One thing you really should consider for an SBR is an adjustable gas block. I have a 10" 5.56mm rifle and with a standard gas block, the gas was somewhat manageable when i would shoot once, every 5 seconds or so but when i get into rapid fire, the gas was unbearable for me at least. An adjustable gas block is not necessary but will for sure help from irritating your eyes. I have a spikes tactical adjustable gas block, and i tuned it to run correctly with and without my suppressor and it works great without excessive gas.

 

[OnyxSkyDV]

Re: SBR build questions

Killer makes a good point. This just came out at SHOT this year from what I was told, and sounds like a good deal if you consider it takes the place of an adjustable gasblock.

http://palmettostatearmory.com/index.php...e-receiver.html

Onyx

 

[killerwaffles]

Re: SBR build questions

Oh wow, on the receiver, that is sweet! Definitely doing that for my next SBR build

 

[OnyxSkyDV]

Re: SBR build questions

Apparently you can turn it with your fingers too, no tools needed. Debating on one myself. Would be nice if they had a no gas setting, but sounds like turning it to between settings will do that. Sounds kludgy though.

Overall I like the concept.

Onyx

 

[jasonZ]

Re: SBR build questions

Well shoot now my build just went up in price! That's pretty sweet to be built in to the upper. Thanks for the info guys, I never thought about an adjustable gas block for it!

 

[OnyxSkyDV]

Re: SBR build questions

sounds like it's fairly close in price to an upper and a adjustable gasblock together. So not too much more.

Onyx

 

[killerwaffles]

Re: SBR build questions

You will be glad you spent the extra cash on something that will benefit you. Also if you are running a suppressor, i would look for a faster twist rate of the bullet just to be sure it will stabilize. 1:8 should be good enough but i wouldnt go anything slower than that. Also, just remember the shorter the barrel, the more gas and louder the muzzle blast is going to be.

I have a couple uppers for my sbr lower that i can swap out. I have a 5.56mm and a 300 blk that i use. That would probably be the easiest thing. I have never had a problem with matching the bolt to the barrel. I literally just dropped in my parts and they seem to run fine. Not to say it isnt needed, but i have not had an issue with matching parts.