great plains rifle sights

[Justin]

I've been shooting low with my great plains rifle. I have the rear sight adjusted to the max and was reading about filing the front sight. Is it normal to have to file the front sight to get proper elevation at 100yds. I have been using 100gr of powder shooting conical bullets. I've tried different types of conical and am most accurate with hornady 425gr. I'm shooting about three inches low at a hundred yards. Any suggestions?

Justin

 

Well the GPR is a slow twist rifle best suited for RB, and the GPH with a 1:32 is better for the longer projectiles like you describe. I don't want to get into that whole argument again so just let me say: if yer shootin them loads out of a gpr and are getting a satisfactory group then yes file the sight.
The folks around my neck of the woods do find the lyman factory front blade to be a bit basic. It's big and blocky. Many guy's thin the blade and file the top down a bit too allow more adjustment with the rear.
Remember you can't un-file so go slow,,replacement sights for the front dovetail blade can be found on about a dozen web sites or stores fer about ten bucks,,,so,,go ahead,,hack away,, hands on practice and experiance is worth 10$.
luck too ya,,,,

 

You say it's a Great Plains rifle. If it's really a Great Plains rifle then you should be shooting a patched roundball as the GP Rifle is NOT made for conicals.If you have the GP HUNTER then the twist is 1:32 and is a bullet shooter.
If you're out of adjustment on your rear sight then yes you need to file down the fornt sight a LITTLE bit.
Go slow as it's a lot easier to take metal off than to put back on.
1/16th should be plenty to start. Shoot and go from there.

 

[2172]

my GPR shot so low that I used a Dremel tool cutting wheel to reduce the front sight by about half...worked great...but, as you've been told, you can't put it back on if you take too much off, so go slowly...Hank

 

I believe Brownell's has a sight height calculator that will allow you to determine exactly how much to remove to get the POI adjusted. Poke around on their website to find it.

www.brownells.com

 

Put it this way - it is abnormal not to have to adjust sights on a rifle or handgun.
: Normally, the top of the rear sight must be a few thousanths higher than the top of the front blade(or centre of the bead). That will usually put you on at 25yds. and again around 50 yds., depending on stock shape and recoil mechanics of the stock/load.

 

[BrownBear]

I'd settle for three inches low at 100 yards if it is hitting where you want at closer ranges. Based upon my GPR 54, my groups with conicals were so bad at 100 yards, I couldn't tell if it was shooting a little low or high. That slow twist simply works better with PRB. Consider this: I was shooting mine last night at 100 yards with my new tang sight and globe front, just to see where it was hitting in relation to my 50 yard sighting. I was mightily impressed that the largest of three three-shot groups was 2 1/2", measured to the outer edge of the holes (call it wiggling when I should have, but the smallest was MUCH smaller).

If you want to mess with long range shooting, here's an alternative to filing the front: Replace the sight adjustment screw with a longer one. I went to a large hardware store with those multi-bin screw assortments, from which you can buy individual screws. I wasn't sure about diameter or length, so I bought a range of them (metric sizes) for pennies each. I was able to use the sights out to 150 yards, just for the heck of it.

Sorry I didn't keep track of which was which so I could tell you which one is right. This would let you play a little more before grabbing the file, or potentially replacing a $10 front sight.

 

Maxiball, in Canada, from Wholesale Sports in Calgary, you have the choice of either twist when you buy the GPR, 32" or 66"or 60"(whatever the RB twist is). As well, you can also buy the "other" barrel if you want to have both for the same rifle. Now, this would be a combination I'd like to have had for my English rifle. An inch and and eighth barrel in 32" twist in .54 cal would have made a nice slug gun for up to 600gr. bullets, eh?

 

[Justin]

I am shooting the hunter barrel and had three inch groups today all about three inches low at 100 yds. I was shooting 105 grains of powder and don't have any more sight adjustment. I am goign to attempt the front sight, well see what happens, probably shoot ten inches high. Thanks for the help.

Justin

 

[Zonie]

From what I've read, I believe the GPR factory front sight is intentionally left tall so you can file it down to get the gun to shoot where you want it to.

I don't think I have ever read someone say "...and I didn't have to even file the sight to hit right where I was aiming" when they first shot their GPR.

 

Daryl, as a matter of conversation only,,here in the US when we speak of the Lyman Great Plains model,
the Great Plains Rifle is the slow twist 1:60,
the Great Plains Hunter is the 1:32,,,it's just a common way to refer the differance.
And it's true the barrels are both 15/16 od octagon and can be transferd from one to the others stock. Or the "other" barrel can be purchased for the same stock.
Another little fun fact is the
Green Mountain I.B.S. barrels in 15/16 od made for T/C,Cabelas,Lyman Deersalker can easily be made to fit the "Great Plains" model with a simple change of one or both under-lugs, cutting the rail, and moving the front thimble. The hooked/snail breech style of all the above models are all the same, and will fit in proper position for the lock mechinism. That will give a guy a range of caliber options from .32 >,,gosh I think they even offer a a big cal. smoothy now,,,,,,,

 

[strongarm]

Two thoughts on the subject:
1) there is a difference between a great plains hunter and a great plains rifle from Lyman. the GPR should be shooting round ball and the hunter should be shooting conicals. Conicals work from a 1 to 28 inch twist up to a 1 in 48 twist. Most GPRs have a 1 in 60 twist and therefore should be using round ball.

Second point is that I have had good success by putting wonder wads under my conicals and that helps with accuracy and with raising them up a bit. Like about 3 inches.

strongarm