Magnum AR Project
- Thread starter Masczek
- Start date
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ok...one more time...
For the OP to get his WSM AR10 to shoot properly, with a load that exceeds 55Kpsi...
He's going to have to install a rifle buffer and stock on his gun, with a minimum 9 oz buffer, and a good spring (Tubb's Flatwire)
Along with an adj gas block and a full mass BCG..and try not to jam the bullet which build a pressure spike, that seems to raise cain with how AR's operate
cohunt
Well-Known Member
My 308 handloads are close to the saami max 62000psi,-- and my rifle operates perfectly with a ti bcg and 1 oz carbine buffer and stock carbine spring, 16" bbl with midlength gas system and adj gb
In an AR, a 308, and a WSM, at 62,000 psi are not the same animal.
cohunt
Well-Known Member
I understand, but the way I read it-- you were saying anything over 55000 required rifle length
I know that kak sold theirs with carbine tube but rifle seems to run more smoothly in most any rifles
Here is another thread that might help the op
300 WSM AR10
I have an itch to scratch. I have all the components to build a lightweight AR10 (yes Armalite) in 300WSM. I have a 10T barrel, reamer, GG, barrel extension, superlative adjustable gas block, KAK magnum BCG, and Armalite build kit. Even have 100 pieces of 300 WSM virgin brass. Those of you who...
Actually, I am saying that any A.R. 10 in a magnum, needs a Rifle Buffer tube, and a minimum 9 ounce buffer.
cohunt
Well-Known Member
I
the kak rifles had carbine tubes/buffers/springs and cycled fine, and I've seen quite a few more wsm uppers cycle correctly with carbine tubes/buffers/springs.
The rifle length might help, but they can function with carbine system. I'm not trying to be argumentative, I'm trying to understand the reasoning behind your statement (unless I've missed that somewhere)
I've heard the big drawback of prior wsm ar's was the use of 308 or modified 308 mags-- but the op may have fixed the mag issues by using aics mags.
It might be good to explain your reasons, so we can understand also--
the kak rifles had carbine tubes/buffers/springs and cycled fine, and I've seen quite a few more wsm uppers cycle correctly with carbine tubes/buffers/springs.
The rifle length might help, but they can function with carbine system. I'm not trying to be argumentative, I'm trying to understand the reasoning behind your statement (unless I've missed that somewhere)
I've heard the big drawback of prior wsm ar's was the use of 308 or modified 308 mags-- but the op may have fixed the mag issues by using aics mags.
UncleDano
Well-Known Member
Dwell time is defined as the amount of time a bullet spends in the barrel once it passes the gas port.
Well that seems the opposite of what would be intuitive, but being poorly informed I'll accept it until I discover otherwise.
There's different types of dwell. Yes, time in the barrel is 1,but I guess you could call the other lock time if that'll help. For now just call it "lock time".
Any updates?
Masczek
Well-Known Member
Haven't had a lot of time to do some extensive testing, but here's a video I got of it last week.
This is the 6.5 PRC upper, it works a bit better, but is still over gassed. I tried both the Griffin Armament +15% extra power spring, and standard AR 308 carbine spring, both seem to operate the same when firing. I've got the Superlative Arms bleed off adjustable gas block installed on it now, so I'll see if this helps the over gassed issue by bleeding the excise gas out. I'm also going to try this on my 300 WSM barrel as well. I haven't ordered another test barrel yet, but I can get one with a .064 sized gas port. I'll start testing with that and drill the hole bigger if I need too.
I've decided to try all of this before going with a rifle length buffer tube and much heavier buffer, I'd like to see how my theory works with the bleed of gas block and smaller gas port.
This is the 6.5 PRC upper, it works a bit better, but is still over gassed. I tried both the Griffin Armament +15% extra power spring, and standard AR 308 carbine spring, both seem to operate the same when firing. I've got the Superlative Arms bleed off adjustable gas block installed on it now, so I'll see if this helps the over gassed issue by bleeding the excise gas out. I'm also going to try this on my 300 WSM barrel as well. I haven't ordered another test barrel yet, but I can get one with a .064 sized gas port. I'll start testing with that and drill the hole bigger if I need too.
I've decided to try all of this before going with a rifle length buffer tube and much heavier buffer, I'd like to see how my theory works with the bleed of gas block and smaller gas port.
Are you using factory ammo or rolling your own? If you feel it's still overgassed then try a faster burning powder that'll have less volume and less pressure at the gas port. For the 6.5prc ar10 barrel I've ordered (22") with a +2 on gas the port size is .100". I feel I might not be able to use a carbine buffer due to no weighing enough, but I'll find out when the time comes (7/5/23 for expected arrival)? I can and will send you a very heavy rifle buffer to try if you want to? It'll also let me know if it's needed? Always willing to help a fellow shooter and designer!
