11 inch X39 buffer weight

[Dutch110]

I have a 16 inch x39 build that is freaking awesome. CLGS with a port size of .093. Running a standard carbine spring and an H2 and is cycles flawlessly.

Currently in process of building an x39 SBR with an 11 inch barrel. CLGS with unknown port size (it's in the mail currently) but will make sure it too is sized at .093. I want to go A5 with this one and am planning on using a sprinco green. Looking for thoughts on buffer weight. I am thinking the 5.3 oz should be ok. Shooting mostly steel cased but do run brass as well. My thought is gas pressure at the port should be similar between the 11 and 16 but this is just me making some assumptions. Anyone have any thoughts on this? Worst case scenario I have a buffer collection at the end of the day.

*Update* I bought the barrel from KAK and sent them an email asking about port size. Just got a reply back from them that it's .078.

[Alpine2k3]

I have a 10.5 in that caliber. I'm using H2 with a colt carbine spring and it has worked well so far. You could probably use the A5H2 with it.

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[Dutch110]

I have a 10.5 in that caliber. I'm using H2 with a colt carbine spring and it has worked well so far. You could probably use the A5H2 with it.

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Thanks for that. That was my plan as well. For fun I called VLTOR yesterday (they were great) and laid out my plans as mentioned above. They actually suggested starting with the A5H3 and going from there. Which kind of surprised me as well. I already have an A5H2 in another build so I may pull that and try it out first before buying the A5H3. I wish more people would make decent barrels in this caliber. Faxon was the only other one I could find and they are perpetually sold out. The fact that KAK makes them with a .073 port size pretty much tells me they don't feel like changing the bits on their press lol.