Just as was ready to click on the pay button, my wife tells me that her LG washing machine sprung a leak. Upon inspection I found that the LG imploded and spilled its guts all over the laundry room and I had to replace it. So, I have to cut way back on new build. I am hoping that I can use my Springfield Armory Saint AR15, which has a carbine length buffer tube/spring lower and a 16" bbl with mid-length gas system, on a aero precision 20" complete upper which is a rifle length gas system. What say all you experts ???
Will my Saint AR15 lower "run" a 20 inch bbl rifle length gas system upper??
- Thread starter charliebrown1999
- Start date
Yes, a rifle upper will run on a carbine lower. In fact, they're made in that configuration for the Canadian military. Your only trouble is that you may experience some malfunctions depending on the weight of the buffer, but you ought to be fine. You may want to swap the buffer for a heavier carbine one for better performance. (pic is from wikipedia)
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You’ll be fine, in fact it should run smoother with the Rifle length gas system.
It seems to me that a rifle length gas system would have the least amount of gas pressure so a heavier buffer would not be necessary as I will never be running a suppressor as they are illegal here in CA.
Americans are illegal in California.. but if your worried about your ar get a jp silent spring buffer. You can buy different weights for em and then get a adjustable gas block and tune it as light as it will still lock bolt back after last round. If after reading all these comments your still worried, buy a rifle length buffer tube.. I built a 17 Remington ar upper with a 26” barrel and rifle length +3 gas system and lightweight bolt and it still cycles. (I was going for real light recoil). Don’t be scared to try things with your big kid LEGO set!
The buffer for the rifle length gas system weighs about the same as an H3 carbine buffer at 5oz.
You should be GTG, and a heavier buffer would just help make the perceived recoil impulse feel "lighter"... rifle stocked AR's use a 5.2oz buffer.
I have run some pretty heavy weights and never had an issue, in average "t-shirt" weather.
The biggest "factor" would be the new uppers gas port size. Anything wildly out of specs would alter your results.
Aero is typically within specs gas port wise.
I have run some pretty heavy weights and never had an issue, in average "t-shirt" weather.
The biggest "factor" would be the new uppers gas port size. Anything wildly out of specs would alter your results.
Aero is typically within specs gas port wise.
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