Gas tube roll pin problems

[ThePhantom]

After hours of hard work i finally got the taper pins out of my a2 front sight for my project AR. The new gas block fits like a glove, and just when i thought the tough part was over I came to the part where you put the roll pin in that holds the gas tube in place. I have been at it for over an hour and I can just not seem to get the little sucker in. I would like to be able to do it without ordering a special tool and waiting 3 weeks. So if there are any DIY ways of putting this sucker in without a tool it would be greatly apreciated.

 

[ThePhantom]

UPDATE: I used the roll pin from the A2. Its not as long but it fit better into the tube. Its not Loose or anything so I dont think I need to worry about the tube slipping out of place. It covers one side. If this was a big mistake that can result in my gun blowing up or something I would love to know before I test fire it. But from what I can tell the pin works fine. There isnt any play in the tube, The other one just would not fit in the tube hole.

 

[Ibmikey]

Roll pins often require placing a bevel on the end you will insert. Another trick is to put a punch in the hole up to the tapered shank and tap smartly. This will give you a angled entrance to the hole. Larger pins can be squeezed but that may be difficult with a small pin like the one for a gas tube. Also the pins you took out of the FSB are normally tapered and some manufacturers put them in in opposite directions, they should not take hours to remove.

 

[ThePhantom]

Okay, Thank you sir.

 

[Plazzman]

Rule of thumb, if you are removing taper pins from your A2 sight, look for the smallest diameter end of the pin and drive it out from that side. You have to remember these pins are tapered, one end is larger that the other.

 

[Maddmax]

You DO NEED to put the roll pin back in. They are in there so they expand and contract with the heat. The are by shape/design made to stay put. In short time the taper pins WILL work loose do to the taper of the pin,along with the contraction of heating and cooling along with vibration from the muzzle harmonics and it's blast.

Try different ends of the roll pin. Try both sides of the gas block. Beating it out,did you get a lip on the end of the roll pin from beating on it with too large a punch or expand it using too small a punch ? A light file or fine emery paper will remove that lip.

Remember there is a boat load of pressure on that gas block when you pull that trigger. Think what could (eventually will ?) happen....

Do it right. Some times you don't get a second chance or you have to live with what could have been a fixable mistake. "Fit better" don't always count or work as planned.

SAFETY FIRST,LAST AND ALWAYS.

 

[apiccola]

You can also try chilling the gas tube, gas block and pin in dry ice or your freezer for 30 minutes prior to assembly. The metal parts will contract slightly allowing better clearance to position the pin without adding stress to the assembly.

 

[WR Moore]

You can also try chilling the gas tube, gas block and pin in dry ice or your freezer for 30 minutes prior to assembly. The metal parts will contract slightly allowing better clearance to position the pin without adding stress to the assembly.

Uh, you generally chill the part you're inserting, in this case the pin. The part you're placing the pin/shaft/whatever into is heated. Niether is necessary with a roll pin otherwise known as a spring pin where the part is held in place by tension.

Do make sure you have the notch in the gas tube in the proper place.

A bevel on one end of the pin as suggested earlier helps. Hold the pin in place with needle nose pliers or hemostats and gently tap to start.

 

[JaPes]

Also helps if you use a roll pin starter punch.