Best Gas Tube Roll Pin Install Method

[BluntForceTrauma]

Am buggering up the gas tube roll pin installation of my last three builds and need advice for the best method. My roll pins always end up sticking out about 1/32 inch no matter how much I hammer them with my little Lyman gunsmith mallet and a brass punch. I try to finish them off with a small steel punch, but it just bounces off the pin and mars my beautiful Vltor gas block.

I've been trying a method where you brace the block against a wood block, then bend a paper clip so that it comes up thru the gas block roll pin hole and sticks out just enough to hold the roll pin in place for that first critical whack.

What do you guys do cuz I'm frustrated?

[Bigs28]

I just use channel lock pliers. Put some painters tape on them to not scuff up the gas block or lower receiver.

[-Justin-]

Vise-grips, electrical tape, and steel punch works decent. Just broke down and bought a set of Geissele gas block punches among some of their other tools though.. will find out later this week how well they work.

[ricsmall]

I have a set of wooden blocks to fit my bench vise that are flat on one side and have a V cut on other side running parallel to vise jaws. Use v on one block and flat on other to hold gas block. I use a roll pin starter punch to start then finish with a regular roll pin punch.

[A5BLASTER]

Geissele punch's is what I use. Still a pain in the butt sometimes. I use the joeboboutfitters roll pins.

A screw and nut system would be just the trick for this kind of install. Lil red locktite and done. Simple and fast.

[mv1arms]

I had had this problem in the past. Try rounding the edges of the roll pin with a file on the leading side. It makes it go in a lot smoother (that's what she said) and reduces the chance of it requiring enough force to bugger up the punch side.

[Lemonaid]

https://www.brownells.com/gunsmith-tools-supplies/general-gunsmith-tools/punches/gas-block-assembly-fixture-prod58351.aspx

You can make your own starter pin punch with the right size drill bit and a rod. A drill press will aid in getting a straight hole.
A set of roll pin punches are a good investment. Using a roll pin punch one size smaller than the one to get it started will aid in finishing without flaring the end of the roll pin.
If having problems with alignment, a "slave" pin helps a lot. Gunsmiths often have a box of pins of various lengths and diameters for aid in re-assembly of firearms. Making you own is pretty easy (the paperclip method mentioned in OP is a slave pin, but might not be correct diameter to work best.).
As Mv1arms posted, beveling the leading end of the pin will aid in getting it started. That can fix a pin that has been slightly damaged on the end.

[montana]

https://www.brownells.com/gunsmith-t...prod58351.aspx

You can make your own starter pin punch with the right size drill bit and a rod. A drill press will aid in getting a straight hole.
A set of roll pin punches are a good investment. Using a roll pin punch one size smaller than the one to get it started will aid in finishing without flaring the end of the roll pin.
If having problems with alignment, a "slave" pin helps a lot. Gunsmiths often have a box of pins of various lengths and diameters for aid in re-assembly of firearms. Making you own is pretty easy (the paperclip method mentioned in OP is a slave pin, but might not be correct diameter to work best.).
As Mv1arms posted, beveling the leading end of the pin will aid in getting it started. That can fix a pin that has been slightly damaged on the end.

Yup, I use the same Precision Reflex GAS BLOCK ASSEMBLY FIXTURE. Roll pin starter punches work great for all roll pins.https://www.amazon.com/Wheeler-Engin...gateway&sr=8-3 I have noticed some roll pins are a little tighter than others which can be eased in with a little oil or grease. SLR roll pins are very tight compared to others that I have used. If push comes to shove, I would run a drill bit by hand through the hole to open it up just enough.

[FLshooter]

I use a grace 5/64 roll pin holder and drive it in w/a 8oz brass hammer.Then I finish it off with a 5/64 roll pin punch.I believe Brownell also sells roll pin holders.

[Klem]

I use a Security Torx bit to hold the pin and act as a punch. The Security version has a hole in the top where you put the roll pin. The depth of the hole holds about half of the pin. Tap it in until the bit comes up against the gas block then take it away and finish with the hammer.

A cheap set is a few dollars and you can also use them for scope screws. I can't remember exactly which one but there is one in the set that holds the pin snugly.

[BluntForceTrauma]

Thanks, guys, sounds like this is a task where it's cost-effective to just get the right tools for the job rather than trying to cobble something together and make do.

[D.Davis]

BFT, Brownells has a roll pin starter set and a gas block set. I bought the set and use it for AR assembly. Dave.

[Djgrendel]

Great thinking Klem! Never even crossed my mind. I usually drill out 4140 round stock to hold various diameter pins. Your method wins for simplicity!!

[Triticum]

As if getting the pins IN wasn't hard enough, ever try to get one back out? I've never been able to do it without at least ruining the pin, if it can get it out at all.

My solution, tap the pin hole in the gas block to 4-40 on both sides. Put a short 4-40 grub screws in. If you grind a cone shape on the bottom of the grub screws they will lock into the hole in the gas tube and this usually lets the screws go in far enough to sit flush with the outside of the gas block. Best part is you can take the thing back apart someday if you need to.

[41bear]

A roll pin starter punch, bough a set, plus I put a dab of RCBS sizer lube on the end of the roll pin and it slides in with no problem. I install my block first, after making sure the tube slides into the GB without a hitch, so my tube will line up properly and it's worked great for me. I had your problem also when I started, good luck.