Function problem with a .308 build:

[Sgt Dog]

Seadog, that is exactly how I measured mine. (0.077 I think it was).

I’d read that first link in that thread I posted. With 20” you have two more inches of dwell time to add to gas pressure. Might call for slightly smaller port size. There are tables there with lots of reference.

 

[Seadog]

Seadog, that is exactly how I measured mine. (0.077 I think it was).

I’d read that first link in that thread I posted. With 20” you have two more inches of dwell time to add to gas pressure. Might call for slightly smaller port size. There are tables there with lots of reference.

Well krap. I don’t have the drill bits yet. I found a link that had the port sides for every barrel. From 556 to 308. I snapped a small picture of it for referencing the 308, 20” .750 diameter. So this is wrong? I’ll see if I can see the link you are talking about

 

[Seadog]

Seadog, that is exactly how I measured mine. (0.077 I think it was).

I’d read that first link in that thread I posted. With 20” you have two more inches of dwell time to add to gas pressure. Might call for slightly smaller port size. There are tables there with lots of reference.

There is a lot of fantastic info that you can get lost in on that link you posted. I’ve been reading on and off there for the last few hours. There’s even more links to drag you into other areas. I love learning and there was an interesting topic over there about the length of the gas tubes that I was not aware of. I went and checked some of my rifles and sure enough one of them has a gas tube that appears to be quite a bit short for a rifle length gas tube. That could possibly explain why my other AR 10 is also short stroking and not loading the round all the way.

What is funny is that link you posted is a link that I’ve already found and it is where I had took the picture of the gas port hole sizes listed. I haven’t read through it before but had just been looking for the proper hole sizes. This time having gone to it and read through it, that’s when I discovered that it is where I got the picture from.

 

[Sgt Dog]

There is a lot of fantastic info that you can get lost in on that link you posted. I’ve been reading on and off there for the last few hours. There’s even more links to drag you into other areas. I love learning and there was an interesting topic over there about the length of the gas tubes that I was not aware of. I went and checked some of my rifles and sure enough one of them has a gas tube that appears to be quite a bit short for a rifle length gas tube. That could possibly explain why my other AR 10 is also short stroking and not loading the round all the way.

What is funny is that link you posted is a link that I’ve already found and it is where I had took the picture of the gas port hole sizes listed. I haven’t read through it before but had just been looking for the proper hole sizes. This time having gone to it and read through it, that’s when I discovered that it is where I get the picture from.

I thought some of it was pretty good reading. A lot of it was new to me. There were rabbit trails, for sure. Glad you got some use out of it.