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snaketail
05-27-2013, 06:24 PM
I shoot a .45 Colt lever gun with a tang sight in Cowboy Silhouette matches. I've been shooting 230gr LRN for the shorter range Pistol Cartridge matches then changing to a 250gr for 150 and 200 yard targets. The problem is I'm at the top of the sight adjustment on 150 yard turkeys and need to hold high on the back of 200 yard rams. I need to fix this.

I'm thinking of changing to a heavier boolit, like 300gr. The reason being that more recoil should elevate the Point of Impact - it does on my handgun. I'm not worried about taking the long range targets down, the lighter 230gr will knock them over (with a rainbow trajectory) - I'm just looking to elevate the point of impact.

Do you think a 300gr boolit at 750fps will raise the point of impact a couple of inches over the 250gr/750fps boolit?

M

pietro
05-27-2013, 06:36 PM
How about installing a folding rear bbl open/iron sight, and zeroing the open sights for the shorter range, and the tang sight for the longer range(s) ?

It shouldn't take but a moment to flip the open sight "down" with the hand on the forend, and the tang sight "up" with either hand for the longer shot(s).

In reality, with it's higher line-of-sight, the bbl sight might not even need to be folded to use the tang sight, so speed might not be an issue.




.

RickinTN
05-27-2013, 06:39 PM
I've not done what you are referring to so I can't answer you with certainty. I think the slower heavier bullet will go the other way, you'll need more elevation to get it zeroed. I do agree that recoil/bore-time have an effect on where a particular gun shoots a particular load, but I also think you'll find it much more pronounced in a handgun than in a rifle. There's only one way to find out and that is to try it and see what happens.
Good Luck to you,
Rick

Nobade
05-27-2013, 06:41 PM
As long as your 40M chicken zero isn't all the way down now, why not put on a shorter front sight?

-Nobade

fecmech
05-27-2013, 07:34 PM
As long as your 40M chicken zero isn't all the way down now, why not put on a shorter front sight?

Or simply file your front sight shorter if it's a post type.

Buzzard II
05-27-2013, 11:41 PM
You may want to contact Montana Vintage Arms for a taller tang sight. Buffalo Arms also has an assortment of various height front sights.

smoked turkey
05-28-2013, 12:57 AM
I also had a similar situation on a Savage 30-30 and I simply shortened the front sight by filing it down and touching it up with cold blue. I then painted the top of the lower sight with white paint and it seems to work very good now with the rear sight elevator in the middle position.

NickSS
05-28-2013, 04:53 AM
you are running out of elevation on the tang sight you have. My experience with heavyer bullets is that you need more elevation than less for any given range in a rifle. It's different in a handgun and they have much more muzzle jump and they are light weight so heavyer goes higher. You can either lower the front sight or put a longer tang sight on your rifle. Buffalo Arms sells a marbles tang sight with interchangable posts that would work good you what you are doing and they are much cheaper than almost any ladder type tang sight you can get.

Larry Gibson
05-28-2013, 12:11 PM
Do you think a 300gr boolit at 750fps will raise the point of impact a couple of inches over the 250gr/750fps boolit?

No, rifles recoil differently than handguns (your comparison) and the lower velocity will mean more elevation is required at 200 yards. I also suggest altering the front sight by making it lower. I would set the tang sight at its' lowest setting + about 3 moa up and then file down or replace the front sight for a zero on the 50 yard (?) chickens. That will then leave maximum elevation adjustment in the tang sight. Should be enough then for the 200 yard rams.

Larry Gibson

snaketail
05-28-2013, 03:06 PM
Rather than file on the sight I'll just replace it... I have a thing about making unreversible changes to my firearms. My next thought was "which height should I buy?" My internet search turned up this info. http://www.rossi-rifleman.com/viewtopic.php?f=9&t=479

Thanks for the help.

Michael

snaketail
05-28-2013, 05:04 PM
I think I'll do both, and shoot the 230gr

snaketail
06-01-2013, 09:54 AM
Went to the local boolit store yesterday. He has 180 and 200gr LFN boolits, powder and primers - whoo hoo. Bought some of each and will try the lever gun with some fast moving loads today.
I have two expectations/hopes/desires: (1) the faster loads will mean less elevations adjustments, and (2) supplies are returning to normal!
If I can have #2 I'll make-do with #1.

M

PS - Bears? What bears, we ain't got no stinking bears.

snaketail
06-01-2013, 04:11 PM
Oh, those bears - The 180gr Boolit patterns similar to my sporting clay gun. The 200gr did much better - but the bears were out in force and I ran out of test ammo at 100 yards. Starting to think I should stay with the 230gr boolit and stop messing around with "soft"loads. At least now there is powder to experiment.
M