Question about pinning a gas block on an AR build

[FormerNavy]

What do you guys use to hold everything in place while pinning a low profile gas block on a barrel?

I've built several ARs and I've always had barrels with the cutout pre-drilled for pinning the LPGB and I've always pinned them. But frankly it's been a real pain the rear as the barrel or block tends to roll around or move while trying to keep the LPGB aligned and driving the pin in. So it got me thinking.... for those of you that build ARs, what do you do to keep everything aligned and not moving while driving the pin in? I've looked at some of the blocks designed for assisting with getting the gas tube roll pin installed and I wonder if that would work but I'm really not sure.

[Mr. Glock]

If the upper is in a vice block, with the barrel attached, then the barrel is not going to move. Depending on how your vice is attached to your workbench, you can "build up" a support for the LPGB. Nothing wrong with a little chisel work on a 2x4 offcut either.

That said, I've not had much issue with starting the pin prior to putting the gas block on the rifle, then doing it right on the bench with a hasty made rest. The hard part of it is getting the pin in hole, but you have a little space to start it and hold it, ready to mate with the barrel cut out when you put it on the barrel.

If I'm understanding your question correctly.

[calvin56]

If you are having problems keeping the block and the barrel aligned while tapping the roll pin slide a slightly smaller pin (blunt end of a drill bit) in from the other side. Hold the bit while tapping the already started roll pin until no longer needed.

[MyWifeSaidYes]

Or use something like this:

https://www.youtube.com/watch?v=nk-lNYPz9OM" onclick="window.open(this.href);return false;

[expo2248]

I grind a slight taper on the leading edge of my roll pins so they start into the hole straighter and easier.