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am44mag
10-01-2017, 07:03 PM
I bought an older .45 cal Lyman plains rifle awhile back for a pretty good price, but it has a few issues that I can't quite figure out.

I cannot cock the hammer without first pulling the rear trigger. When I pull the rear trigger, I can hear two distinct clicks. If I pull it only to the first click, I can cock the hammer. ANY slight bump will cause the hammer to fly forward though. Definitely not something you want to happen when the gun is loaded. If I pull it to the second click, the hammer locks solid and will not drop unless I pull the front trigger. This is the first cap lock gun I've ever owned, but that doesn't seem right. Shouldn't the hammer lock back before you fully pull the rear trigger? I thought the rear trigger served to lighten the weight of the front trigger right before you want to shoot?

The second issue is accuracy. I cannot hit the broadside of a barn with this thing, and I don't know why. I've tried the lee REAL bullet, and a LEE minie ball both over varying charges of real black powder. I've tried cleaning between shots, and I've tried not cleaning. I can sort of hit a target at 50 yards, but 100 yards is beyond what this rifle can apparently do. I know I'm not that bad of a shot, and the sights on the gun are actually pretty nice, but I cannot get this thing to shot accurately for me.

Deer season starts at the end of October, and I would like to avoid buying a cheap inline.

725
10-01-2017, 07:14 PM
I can't remember which model Lyman was a slow twist (made for round ball) and which had a faster twist for the conicals. If you have the slow twist barrel, I doubt you'll get much accuracy trying the various conicals out there. The good news would be, if you have the slow twist, it will shoot round ball like a house-a-fire. Round ball is a terrific hunting projectile.

Can't help you with the trigger thing. Don't know much about Lymans.

am44mag
10-01-2017, 07:23 PM
I can't remember which model Lyman was a slow twist (made for round ball) and which had a faster twist for the conicals. If you have the slow twist barrel, I doubt you'll get much accuracy trying the various conicals out there. The good news would be, if you have the slow twist, it will shoot round ball like a house-a-fire. Round ball is a terrific hunting projectile.

Can't help you with the trigger thing. Don't know much about Lymans.

Did a little digging, and I think you're right. I saw a post on another forum where the guy said that all Lyman plains rifles (not great plains) were 1:60 twists. I'll buy a mold and see how a round ball shoots out of it. I just need to figure out if I need a 440" or a .445" now.

Thanks!

KCSO
10-01-2017, 07:28 PM
Your set triggers are not set up right. The set trigger should only click once as it drops into the front trigger notch. Being unable to cock the gun with the triggers unset is the rear trigger bar bearing on the sear. You should have a small set screw to adjust this if it is missing you need to get one. It will lift the set spring just enough to let the rear trigger bar float under sear pressure and still hammer the sear when released. Unfortunately to repair the problem we need the whole rifle to adjust and test.

am44mag
10-01-2017, 07:31 PM
Your set triggers are not set up right. The set trigger should only click once as it drops into the front trigger notch. Being unable to cock the gun with the triggers unset is the rear trigger bar bearing on the sear. You should have a small set screw to adjust this if it is missing you need to get one. It will lift the set spring just enough to let the rear trigger bar float under sear pressure and still hammer the sear when released. Unfortunately to repair the problem we need the whole rifle to adjust and test.

Where should I find the setscrew at? Is it on the inside of the gun, or is it accessible from the outside?

Edward
10-01-2017, 07:56 PM
Where should I find the setscrew at? Is it on the inside of the gun, or is it accessible from the outside?

On mine it is between the 2 triggers ,adjust with screw driver or better yet google the adjustment first

Maven
10-01-2017, 08:18 PM
am44..., Unless your rifle is very different than mine (Lyman GPR), the screw to adjust the set trigger is where Edward said it is. However, that "screw" is typically too short to make a difference. The simpler solution is to purchase a longer one, but it is an odd pitch/thread. Better yet is to drill and tap for a 6-32 bolt, which can easily be obtained (and shortened if necessary) at your local hardware store.

bedbugbilly
10-01-2017, 08:22 PM
As they've already pointed out, your triggers need to be adjusted. This is done by turning the little screw in the trigger plate between the triggers. Easy to "arm chair quarterback", but if it was mine and it is used, I'd remove the trigger guard and pull the trigger assembly. Clean it well and re-oil. With it off, you can see how the double trigger works and make your initial adjustment with the triggers off the gun. Then put back on and fine tune so that your rear trigger clicks once when setting and the front trigger is adjusted to the pull you want. Then put 'er back together. It really isn't a hard adjustment to make and do a google, there may be a video on the internet on how to adjust that will walk you through it.

I have no idea of what your barrel twist is but more than likely it is a slower RB twist. You may find that your best accuracy will be with a RB. If it is a .45, I'd start with a .440 and play with patch thickness. You should be able to get decent accuracy out to a 100 yards with practice and a proper fitting patch/ball.

Just as a suggestion if you are going to cast. It might pay to buy a box of Hornady swaged RB - one in .440 and one in .445 and see which size is going to work the best in your rifle before you buy a mold. In all of the 45s I've owned over the years, I have always found that .440 worked the best. The only exception is a H & A under hammer I have with a Numeric barrel - they were known to be undersize bores and I'm in the process now of finding what works best in that particular rifle - it will probably be a .437 but I also have a .435 RB mold so my bases are covered. But, every rifle will be different as to likes and dislikes.

Whatever you do, don't get discouraged on it as you'll get it figured out. From your description of your trigger issue, it sounds like it is just a matter of adjusting them so they work correctly. For the accuracy, you might find that RB works the best in your bore and a 45 cal round ball will certainly take care of a whitetail with a well placed shot.

good luck on your rifle and on your hunting!

am44mag
10-01-2017, 08:48 PM
Thanks guys.

I found the set screw, and it was set right. Believe it or not, the issue went away after I took the trigger guard off. I think it was pressing the trigger assembly into the gun just enough to cause issues. Either too far in, or causing it to be out of position. I put it back on and fiddled with it awhile. I finally got it to work by loosening off the front screw of the guard a little. The gun works as it should now. I'm probably going to locktite that screw to make sure it doesn't move, and I'm going to play around with it for awhile to make sure nothing can make that hammer fall.

I guess the safe thing to do for now would be to avoid putting a cap into it until I'm ready to shoot. At least until I know the hammer won't let loose.

Thanks for the help guys, I'll grab some of those Hornady bullets and see how it shoots. :D

bob208
10-01-2017, 08:51 PM
I would try .440 that is what I find works in most of my .45"s. except one it is a h&a underhammer that likes a .433.

nvbirdman
10-01-2017, 09:15 PM
Instead of locktite, how about a washer between the triggerguard and stock?

hpdrifter
10-01-2017, 09:15 PM
Sounds like your triggers are set to deep. I'd fiddle withit some more and confirm that.

A layer of postcard or two might make right. If so, and sure of your self, might take a couple of file strokes to make it right.

TCLouis
10-01-2017, 09:54 PM
I would fully locate the trigger/lock issue(s) and get the "binding" fixed first.

charlie b
10-02-2017, 07:04 AM
Glad you found the issue.

FWIW, when hunting I used to use a 'safety' on my caplocks. It was a little brass drum that fit over the cap and the hammer rested on it. When ready to shoot, cock the hammer, remove the brass drum and shoot. It also made the setup a little more water resistant. I haven't seen them in a long time but you can make one out of PVC, copper or brass. Try a 3/8" pipe end cap.

When shooting from the bench I don't put a cap on until ready to shoot.

scattershot
10-02-2017, 10:36 AM
I,used the same "safety". Mine was an empty .32 ACP case. As others have said, I suspect the twist in your rifle is for roundball, and bullets won't shoot accurately at hunting charges. You can check the twist yourself by using a tight fitting patch on a cleaning rod. Bottom the rod in the barrel and make a mark on it where the front sight is. Then withdraw it until you get 1/4 turn, multiply by 4 and that's your twist.

Good luck!

pietro
10-02-2017, 11:08 AM
.

Wood can shrink slightly over time, so the fact that the trigger issue was abated when the front of the TG was loosened indicates that the issue may be from occurring again via the application of a thin shim betwixt TG & inletting so that the TG isn't drawn as deeply into the inlet.


.

Wayne Smith
10-02-2017, 06:54 PM
At least in .50 the GPR can be had in both 1/60 and 1/45 (I believe those are the twists, I may be a little off). I know because I have both of them for mine.

Check the finish under the trigger guard and the lock, and, for that matter the barrel channel. Water getting in and causing the wood to swell may have been part of the problem.

charlie b
10-02-2017, 08:15 PM
The Great Plains Hunter is 1/32 twist.

am44mag
10-03-2017, 01:23 AM
I'll see if I can't get the binding issue permanently fixed. That shouldn't be too hard. I'll have to try the 32 ACP safety trick. I have plenty of that laying around. :D

Thanks guys.