purpledragon
Well-Known Member
WOW!!!! Very nice looking rig!!
Magnum AR Project
- Thread starter Masczek
- Start date
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UncleDano
Well-Known Member
I would love to get my hands on one of those lowers!!!
TonyRumore
Well-Known Member
I have never seen an AR type gun that takes AICS mags. Thats pretty cool.
I have three Alex Pro MLR AR's in 26, 30, and 33 Nosler. They use their own plastic single stack mag.
The action and magazine are actually long enough to feed 375 H&H length cartridges. I was thinking about rebarreling one of them in 458 Lott.
Tony
I have three Alex Pro MLR AR's in 26, 30, and 33 Nosler. They use their own plastic single stack mag.
The action and magazine are actually long enough to feed 375 H&H length cartridges. I was thinking about rebarreling one of them in 458 Lott.
Tony
Masczek
Well-Known Member
Update:
I've hit a snag after testing a new 300 WSM barrel this weekend. I believe the gun is still over gassed and the gas port in the barrel is too large, but I'd like some input on this theory.
I have a SLR adjustable gas block installed with a +2 rifle length gas tube, I'll adjust it until I can get the rifle to eject (there is no bolt stop, I'm still developing this). The bolt will come out of battery slightly with the empty case still in the chamber. I'll open the gas block one more click and the brass might eject at the 1:30-2:00 position. If the empty case doesn't eject it's stove piped. The brass has a very slightly raised rim where the extractor claw grabs the case rim (dwell time too short). I have a carbine Griffin Armament +15% extra power spring along with a 5.5oz buffer.
My theory is the gas port in the barrel is probably too large, it measures at .115 in diameter. With the port that size, I think I cross a very fine line when I open the gas block one click. Maybe a gas block that has a finer adjustment might help? Possibly a heavier buffer may help too, but I want to try and restrict the gas more. I think if I have a barrel with a gas port around .075 it may solve the problem.
Thoughts?
I've hit a snag after testing a new 300 WSM barrel this weekend. I believe the gun is still over gassed and the gas port in the barrel is too large, but I'd like some input on this theory.
I have a SLR adjustable gas block installed with a +2 rifle length gas tube, I'll adjust it until I can get the rifle to eject (there is no bolt stop, I'm still developing this). The bolt will come out of battery slightly with the empty case still in the chamber. I'll open the gas block one more click and the brass might eject at the 1:30-2:00 position. If the empty case doesn't eject it's stove piped. The brass has a very slightly raised rim where the extractor claw grabs the case rim (dwell time too short). I have a carbine Griffin Armament +15% extra power spring along with a 5.5oz buffer.
My theory is the gas port in the barrel is probably too large, it measures at .115 in diameter. With the port that size, I think I cross a very fine line when I open the gas block one click. Maybe a gas block that has a finer adjustment might help? Possibly a heavier buffer may help too, but I want to try and restrict the gas more. I think if I have a barrel with a gas port around .075 it may solve the problem.
Thoughts?
Ya, the port is pretty big at .115"
There are 15 clicks on the SLR block, putting each click at 6.7% opening. Think of working on carb jets, or cam timing with a 6.7% jump each adjustment…
Also you need a 9 oz buffer minimum…with a Tubb's Flatwire
Brass brand?
What powder type/ weight?
Powder compression?
Psi of the load?
COAL?
Reamer spec? Saami?
Bullet/ weight?
Bullet jump/ jam?
You can send this in a PM if you want.
Thanks
There are 15 clicks on the SLR block, putting each click at 6.7% opening. Think of working on carb jets, or cam timing with a 6.7% jump each adjustment…
Also you need a 9 oz buffer minimum…with a Tubb's Flatwire
Brass brand?
What powder type/ weight?
Powder compression?
Psi of the load?
COAL?
Reamer spec? Saami?
Bullet/ weight?
Bullet jump/ jam?
You can send this in a PM if you want.
Thanks
Last edited:
UncleDano
Well-Known Member
Yes, .075 to .085 sounds more reasonable to me.
I have a KAK 9.3oz rifle buffer I could send you to try if wanted?
Also a jp heavy scs with the heaviest spring could help, but I don't have 1 of those. What about chocking down the gas tube (as in some sort of crimp on the gas block end) as to slow the flow, not volume of gas down? Similar to an orifice. Or something different by the way of an expansion (double the diameter or so for "x" amount of distance?
cohunt
Well-Known Member
Gas hole sounds too big to me too--- on a new design, I would always start smaller than I thought it might need-- it's easy to open them up with number size drill bits-- but once it's drilled you can't go back.
As far as springs--- a stiffer spring will help keep the bolt closed and help strip rounds from the mag if there is a lot of mag spring pressure.
Heavier buffers will slow the bolt unlock time and increase the dwell time but they can also counteract a heavier spring in some ways.
You might try looking at what spring, buffer, gas length system, and gas hole size other companies have used successfully in the past.....oly arms, ditech, kak, and dpms have all had 300wsm/300saum ars in the past-- see if you can find out specs on those.
It seems like the more gas there is in the cartridge/system--- the more finicky the system becomes. It may also depend on what powder you are using--- different powder burn rates and going to create different pressures and volumes at the gas port-- not al powders work well in gas gun systems.
The heavier the buffer and spring, the more gas it will take to cycle BUT the system will be more forgiving to small changes ( I found this while using an ultralight - 1oz buffer in my 308w AR, each powder/bullet combo needs a different setting on the adj. GB to function correctly-- if I put a std buffer back in, my setting are more open, but require less adjustments between loads )
Lighter bullets with faster burning powders are going to need a larger hole than heavier bullets with slower burning powders
As far as springs--- a stiffer spring will help keep the bolt closed and help strip rounds from the mag if there is a lot of mag spring pressure.
Heavier buffers will slow the bolt unlock time and increase the dwell time but they can also counteract a heavier spring in some ways.
You might try looking at what spring, buffer, gas length system, and gas hole size other companies have used successfully in the past.....oly arms, ditech, kak, and dpms have all had 300wsm/300saum ars in the past-- see if you can find out specs on those.
It seems like the more gas there is in the cartridge/system--- the more finicky the system becomes. It may also depend on what powder you are using--- different powder burn rates and going to create different pressures and volumes at the gas port-- not al powders work well in gas gun systems.
The heavier the buffer and spring, the more gas it will take to cycle BUT the system will be more forgiving to small changes ( I found this while using an ultralight - 1oz buffer in my 308w AR, each powder/bullet combo needs a different setting on the adj. GB to function correctly-- if I put a std buffer back in, my setting are more open, but require less adjustments between loads )
Lighter bullets with faster burning powders are going to need a larger hole than heavier bullets with slower burning powders
A place in CO still makes short mags for AR's. I think it's Accurate Shooting Systems or something like that?
Masczek
Well-Known Member
Thanks for the replies. Here's a little bit more info on the current setup:
The rifle has a milspec carbine buffer tube with a 22" barrel. The reloads are 200gr Hornady ELD-X with 60.5gr of H4350. I know it's at the upper end of things, but I want to make sure the system will work with higher pressure loads. I've got an Superlative Arms gas block I'm also going to try.
When I ordered the barrel from X-Caliber, I specified I was using an adjustable gas block. They built me the barrel with the .115 gas port. Before I order another barrel I'm going to call them and see if I can have them drill the gas port around .062. Like you guys said, I can always drill it bigger if I need to.
The rifle has a milspec carbine buffer tube with a 22" barrel. The reloads are 200gr Hornady ELD-X with 60.5gr of H4350. I know it's at the upper end of things, but I want to make sure the system will work with higher pressure loads. I've got an Superlative Arms gas block I'm also going to try.
When I ordered the barrel from X-Caliber, I specified I was using an adjustable gas block. They built me the barrel with the .115 gas port. Before I order another barrel I'm going to call them and see if I can have them drill the gas port around .062. Like you guys said, I can always drill it bigger if I need to.
Masczek
Well-Known Member
Is it a rifle buffer? I have a milspec carbine buffer tube, so I can only use carbine length buffers.
With a WSM, you're gonna need rifle buffer tube and a minimum 9 oz buffer.
Cartridge COAL, or BTO?
Cartridge COAL, or BTO?
It's a rifle instead of a carbine on the 9.3oz
