Set Screw

[rancher]

I have a Lyman GPR and have some questions about set screws. First of all if I were to replace it and get a longer one where could I find one? Like a hardware store or is there some site I could order one from???

This question doesnt have to do with the other stuff but, what would happen if you shot with no set screw at all? Probably nothing right?

Thanks for any help!

 

[Zonie]

I assume your talking about the little set screw that is located next to the nipple?

That screw is a plug to seal off the flame channel which connects the nipple to the powder in the bore.
If you shoot your gun without that plug in place, a tremendous amount of flame and smoke will be blown out making it a hazard for anyone on that side of the gun, and possibly creating a fire.
(Don't laugh. Our Musketman once set a bail of hay on fire by resting his Flintlock on it and then touching off the shot).

You should be able to get a replacement screw from Lyman, or from your local Hardware store IF they carry Metric threaded set screws.
Even if they don't carry Metric set screws, they may have some Metric bolts of the correct size.

The screw in my GPR seems to be a 4mm diameter, but I don't know what thread pitch it has.

If you buy the bolt, and you have a vise, you can clamp the screw in the vise with the threaded end up. Then you can use a hack saw to cut a small slot down the center of the thread. This only has to be about 1/16 of an inch deep.

After cutting the slot, use the hack saw to cut off a very short length of the bolt and use a small file to remove the burrs.
You now have made your first rifle part!
zonie

PS: don't forget to try the screw out to make sure it fits correctly before you go to all of that work to make the set screw.

 

[jtmattison]

I think Rancher is asking about the adjustment screw for the set trigger.
If it is replaced with a longer one you can lighten the trigger to the point where it can become dangerously light or not function at all. If you do go with a longer screw, be careful not to lighten the trigger too much.

HD

 

[Blizzard of '93]

does yer GPR have 2 triggers?

 

[lanedh]

Rancher:

If you're talking about the set trigger let-off adjustment, look for a M2.5 (metric) fine thread screw about 1/2 inch to 3/4 inch long, having a pitch of 0.35 mm between threads. If the screw is too long, you can always shorten the threaded portion so it doesn't extend too far below the trigger plate.

Once you have the screw set to the let-off you want, you might want to anchor it with some kind of thread-locking compound. Auto supply stores carry this stuff but they usually stock only the really tough ones; once it sets you can't break the screw loose without the risk of shearing off the screw head. A drop of shellac will anchor the screw just as well, and doesn't resist readjustment. If you buy commercial thread lock, be sure to find the grade that's least resistant to torque.

If you can't find a metric screw of the proper size, you have two options: A, drill out and tap to the next size larger US NF thread, or B, shoot without using the set triggers, which means the trigger mechanism will be fully engaged. You can always fire the gun by using the rear trigger only.

Brgds, Bluejacket

 

[rancher]

Thanks for the replies, I am talking about the one for the trigger. I see if I can find a longer one then.

 

[lanedh]

What I meant to say in my last para above is: if you aren't able to adjust the let-off to your liking, you can still use the front trigger, it will just pull harder because of full engagement with the rear trigger and it is acting as a lever to force the rear trigger against the sear bar. Check it out and you'll understand what I'm trying to explain.

I'd go the extra distance to get a functional DST.

BJ