Lyman Great Plains .54 cal percussion, missing a set-trigger adjustment screw.

Muzzleloading Forum

Help Support Muzzleloading Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Sep 18, 2023
Messages
24
Reaction score
20
I acquire a used .54 Cal Great Plains hawken rifle that was made from a kit. On inspection of the rifle, I have noticed it is missing a set trigger adjustment screw. I am having difficult in locating a replacement screw.
The part number is #6030164, but it does not say what size the metric screw is. Does anyone have an idea of what the screw size is? Even better, where there might be a replacement screw to get?
Brownell, The Log Cabin, Numich, Lyman nor Track of the wolf have one. Diameter and pitch would help me to find one a hardware store.
 
Oh Lord I do, it's written down on the envelop with 2-3 screws in it I bought from the hardware store,, But I can't find it!
I think it's a 2.5 x the fine thread x long enough size.
Point is, the factory screw is too short to utilize that triggers potential, that's a known.
The second point is, the screw you need is at a local hardware store, ya know(?) an ACE or Arrow or any of them that have that big selection with all the drawers,, if you open the right drawer, there will be a full spread of sizes and length.
Take the triggers out, easy with those, tang bolt and a couple screws, then take the triggers down to the store and surf,, bring a little screw driver with ya,, that'll help,(you'll know if it fit's or not), folks use to remove screws from old tape decks/computers and stereo's an such to rpl that screw
 
Last edited:
I went through this with my Investarm Hawken trigger. If it is the same ACE did not have the screw. It actually was a M2.6 x .45. Get 8mm long or longer and trim it. I ended up with my screw being 6.61mm long. I got my screw from HobbyKing. Very cheap for a package.
DSC_4881.JPG
 
If I remember correctly, several years ago, there seemed to be a problem with the factory screw being too short.

Bob
Yes, they did that on purpose to avoid liability for people that may set up a hair trigger and used an uncommon thread size. M2.6 x .45. Screw needs to be about 7mm long to do any adjustment.
 
Dixon's in Kempton, PA is (was?) a service center for the Lyman GPR rifle. It may be worth telephoning them for the correct length screws. Solution #2 is to polish all the inside surfaces of the lock with a fine Cratex wheel or bob in a Dremel tool, lube, and reassemble. I did the latter and now both the set and firing triggers work as they should, which is to say, great.
 
I remember the screw being too short on a GPR I bought. Gun Works either sold me a longer screw or told me what size it was. I know he solved my problem.
 
So, turn the screw in to reduce, or increase trigger pull?
Turn it in to reduce the length of the pull. Cock the hammer. Pull the rear trigger to set it. Then slowly turn in the screw until the hammer is tripped. Back off on the set screw 1/4 to 1/2 a turn. That should give you a pretty sensitive trigger. That only adjusts the length of pull, not the tension. Then it is a good idea to use some penetrating loctite or nail polish to keep your adjustment on the screw.
 
forrest, if you haven't gotten your screw yet PM me. Yes, the original screw is too short. I bought several of the longer length and it works better now.
 
Question for those following this post: I bought several of the correct size screw to solve the Lyman/Investarms trigger problem. Do you think I should place an ad for these screws? In reading this I'm thinking there might be a lot more folks than me that have/had this [problem. Not looking to make beer money on it, just worth my time.
 
Interesting. I have a GPR that I've only shot a few times to sight it in. I think I'll head to my local hardware store tomorrand pick up a longer one. 2.6x45 you say?
 
Do you think I should place an ad for these screws?
Sure, as long as your liability insurance covers the sale of and advertised use of,, why not?
So which is it? The 2.5x45 or 2.6x45 install you plan to sell that will void the manufactures warranty ,(?)
I bought several of the correct size screw to solve the Lyman/Investarms trigger problem.
Honest,, What is the exact fit you have found ?
 
Last edited:
Sure, as long as your liability insurance covers the sale of and advertised use of,, why not?
So which is it? The 2.5x45 or 2.6x45 install you plan to sell that will void the manufactures warranty ,(?)

Honest,, What is the exact fit you have found ?
The 2.5 will fit....but is actually too loose. The 2.6 x .45 was the correct fit in my Investarms.
 
Interesting. I have a GPR that I've only shot a few times to sight it in. I think I'll head to my local hardware store tomorrand pick up a longer one. 2.6x45 you say?
The hardware probably will have the 2.5, not the 2.6. Go to Hobby King.com, sku#171000972-0 and get a package of 10 for $.32. They will be 14 mm long. Cut it down to about 7mm and you should be good to go. Yes, 2.6 was correct in my case. 2.5 is a very sloppy fit.
 
Back
Top