need help with GPR

alright i finally got to the range today and shot it the only problem is i have a bit of hang time on shooting I.E.. i pull trigger and about 1/2 second later main charge fires. so i drilled vent to 5/64s same thing i am wondering if my hole is in the correct position?(insert joke here)the vent hole is 1/16 above pan and at the rear of pan. i might need to do some dremel work. i couldnt get to a 25 yrd area but at 50 witht the delay i was hitting 2 1/2 low to the right but grouping at about 2" not bad for shooting a rock lock for the first time well any help guys and i will be in your debt.

 

[Steve A.]

I can't really offer any advice. I have noticed my touchhole is located toward the rear of the pan as well. I only drilled mine out to 1/16,and i noticed an improvement.My rifle also shoots low. This weekend i finaly made it out to do some good time shooting it. I started filing down on the front blade. I'm still shooting about an inch low,so it still needs some work. I have the adjustable rear site.I tried clicking it all the way up,but after a certain point the screw just wants to come out,and it's really hard to tell when the site stops raising and the screw starts coming out.I just clicked it all the way down. That way i don't have to worry about adjusting it.I figure i'll site it in for 50 yards then raise or lower poa as needed. Since i know they're gonna ask. What kind of powder are you using? I use goex 3f in the barrel and 4f in the pan. I have tried 3f in the pan,and it works well too even better than the 4f in the wet.

 

I terms of your front sight on the GPR. I had the same problem and filed that front blade down to a nubbin - still shot low AND the sight blade was so wide after all the filing that I could not get a good sight picture. I finally got a new front sight - very low and she shoots like a champ. Also - I did not have to keep upping the main charge. It was getting a bit "pushy", if you get my drift, trying to raise the point of impact by increasing the charge.

 

i am using 3f in the pan and in the pipe. i was hardly using any powder in pan at all. pan went off almost every time but rifle had a delay. i dont want to just start hoggin out the pan without some input, but i think my prime is too far forward.

 

[Walks with fire]

I sounds like your vent is a bit too far back. I don't know what Lymans return/repair policy is but I would check with them before any personal modifacations. That being said it would take a bit of tinkering to get things lined up right. Some good pics of the tang, barrel, lock and vent area would help us a bunch. There is a whole bunch of issues with something like this.

 

[cowpoke1955]

Hi jax,
On my .54 GPR flint kit that I finished has the vent center and above the pan. Check with Lyman customer service and see what they say. I had some hang fires and flash in the pan. I already drilled the vent to 1/16th inch. I coned my vent as others have talked about, hoping to focus the primer flash to the vent hole. I'll try it out this week and see if it improves. I also don't like the thick front sight. Planning to change to a silver blade soon for a better sight picture. Teeeking is half the fun :thumbsup: .

 

[sundowner]

As far as the hangfire I replaced the ventliner in my GPR with the linner from RMC it goes in with a hex tool and with it I get almost the same locktime as with my CVA mountian caplock . I would put about 100 rounds through it before you make changes to the sights .
Charlie

 

Me thinks I brain farted. I was using horn from last year i.e.... old powder the tote I had it stored in had a cleaner bottle leaking :shocked2: might have been wet powder also after I initially cleaned the barrel I loaded it with bore butter forgot about patent breech, it could have some residual butter causing me issues. Well definatley somethin to try at the range this weekend. I also called the Lyman customer service line and I couldnt be happier with their support. Well I also noticed I must of had the gun turned slightly cause I took it outside today and had a good look at it and the flint sits right in the middle of the touch hole. So I hope it is the powder or the bore butter either way i cleaned it real good and protected the barrel with rem-oil. Well I guess this weekend will tell. Sorry for the long post had a lot of info to put out there.

 

[Walks with fire]

Great news and your probably right it's probably just powder contamination or a cleaning issue. Good luck and good shooting.

 

[faw3]

Great point about 100 rounds first, even after 30 something years just shooting my first flint I forgot that one! :shocked2: Everyone has his own way, but I sight in at 75 on most rifles then work on how much hold over or under I'll have to have at 50 and 100 yds with a full and a plinking charge. Ive seen some old front sights that are just a hair taller than the barrel, got to wonder what kind of charge they used, or how close they set it for. :rotf: 5,10 foot maybe? ( I started getting a real good instant fire by useing 2f in pan and not much of it, cut way back on the 3 and 4 f and it worded even better!)Fred :hatsoff:

 

ok went to the range today. she shot great when the flint made a spark :cursing: now i went ahead and order english black flints and that is what i was using. when flint did its job delay was gone what a difference. is there any was i have the wrong flints i have the 3/4 square. the flint points about half way down frizzen at half cock so i think thats fine. i dont know what the issue is but i cant wait to get it done. on a side note i let a couple of feller shot the deacon and the were right well impressed with the lock time :grin: they were tickled pink and a couple of em even got my number and give me theirs and said they wanted to get one themselves.

 

[cowpoke1955]

I went to the range today with my .54 GPR flinter. After coning the vent liner it did improve some what. Now only about 45% flash in the pan :rotf: . Pulling out the 5/64 drill bit tonight. With the flash in the pan, I know the lock is working properly. Just have to get the flash to the main charge. Other than that, I'm getting 1" groups, 4" low and 1" right, at 50 yards. Try it again in a couple of days.

 

[jweston]

My GPR is firing consistently low. Should I try to find a gunsmith with BP experience to swap out the front sight, or is that something any competent gunsmith should be able to do?
BBurg

 

[Rebel]

If you haven't already filed the front sight down that would be the way to go instead of getting a new sight. Also, which rear sight are you using, the adjustable or the primitive one. And replacing the front sight isn't something you need a gunsmith for, just drift out the old sight and drift in a new one.

 

[cowpoke1955]

Rebel is right. Just drift your rear sight right or left for windage and file your front sight to raise the point of impact. No need for a gunsmith. Rebel, were you able to use the primitive sights that comes with the GPR? Mine was too small for the dove tail. Lyman sent me two primitive sights. All were identical, too small. I'm going to TOW for a new front (silver blade) and a buck horn rear.

 

[Rebel]

I had to have a new one sent to me too, but the it worked ok. I think they need some better quality control in some of the steps. But i do not like the adjustable sight at all on them. To much side to side play in them.

 

[cowpoke1955]

I'm glad for you. I like the look of their primitive sight, but all three of the of the sights they sent me were all too small for the dove tail.

 

[markinstettler]

I had the same problem. The replacement they sent me was a closer fit than the site that came with the rifle, but still too short to stay in place. I cut some shim material out of a pop can, shimmed it, and that's how it is at the moment.

 

[d.thomson]

I was told that if you peen the dovetail with a ball peen hamer , alittle at a time it will tighten up the sight.FK

 

[jweston]

I have the adjustable sight. There is play in it, but the I have no trouble with the right-left adjustment, it just consistenly fires low.

BTW While I am treating the GPR as mainly as a learner rifle, I am trying to take care of it, but there have been nicks on the barrel from my ramrod and from the flints. I coat with ballistol when cleaning, but at some point I will need to re-blue those areas. Suggestions?