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HPT
08-30-2009, 02:37 PM
I'm having trouble with vertical placement of my groups. I always shoot 10-shot groups and they are never more than 2.00" wide @ 100 yds (usually 1.75"). The groups are usually 3.00 - 3.50" high. I've tried changing the following variables without much improvement:

Fouling control:
blow-tube, wiping & bore pigs

Powder 70 gr - 75 gr using the following:
Goex 1F, Goex 2F, Express 2F, Graf 2F & Swiss 2F

Milk carton wads & LDPE wads both w/ newspaper wad under bullet

Bullets:
Postel, PJ Creedmore & Brooks Creedmoor
hardness 20:1 & 30:1
.457 & .459 dia

Primers w & w/o newspaper wad:
WLRP, Fed 210, Fed 215, CCI BR2

SPG, Sagebrush & 2 homebrew lubes

Bench & X-sticks shooting


I'm looking for non-load suggestions as I think I've exhausted most of those. I'm shooting a Pedersoli Creedmoor #2 .45-70 that weighs about #10. I'm thinking it's got to do with recoil. Maybe I'm holding the gun too loose? Any shooting advice on prone X-sticks & Bench technique?

If I was to get the 10 shot groups < 2" in height would that be considered about as good as it gets?

Lead pot
08-30-2009, 04:10 PM
I see nothing wrong with what you listed.
The only thing I would add for now is case neck tension and position.

Lp

e15cap
08-30-2009, 06:15 PM
Verticle is ususaly sighting error. Put a scope on the gun to make sure you are on the same aiming point every time. Grip and recoil control have to be consistant shot to shot to get good groups. Best, Roger

coyotebait
08-31-2009, 04:32 PM
Have you checked to make sure the buttstock is tight?
coyotebait

montana_charlie
08-31-2009, 05:16 PM
Do you rest the barrel on the cross stix in exactly the same spot for every shot?
CM

SharpsShooter
08-31-2009, 05:46 PM
Sights are a key item not mentioned in your post. Quality Soule sights combined with a globe front with proper inserts will go a long way toward shrinking groups vertically. Buckhorn sights are notorious for vertical stringing because light changes affect your eyes perception of where the top of the front sight actually is located in relation to both the target and the rear sight.


SS

cajun shooter
08-31-2009, 05:59 PM
You need a shooter who knows what they are doing to watch you shoot the gun. There are many factors that may cause your problem. Some have to do with the rifle and others with you. Without knowing you or your rifle it would be pure guessing. You did not say how you were shooting off the bench. If you have the proper bags so that the rifle can be locked in with you placing your cheek in the exact same spot and squeeze each round off then that should work. The weld of the rifle is very important to good shooting.

HPT
08-31-2009, 07:07 PM
The sights are Pedersoli Creedmoor #430 rear and the corresponding front sight. I've tried .039, .052 & .115 rear arpeture sizes and the cross hair insert in the front. Nothing seems loose in the sights.

I rest the gun about 3" back from the muzzle. The same all the time. I'm thinking that maybe my hold is the problem? Any advice on hold? Do you hold tight against the shoulder or?

There is 1 unexplained thing I've noticed. I never need to move my rear sight left/right but sometimes the next time I shoot with the same load I have to change the rear sight height. I've had to go from a .68 sight setting one time to a .71 setting next time.

I can't notice anything loose. Should I try to shoot with the forestock removed?

SharpsShooter
08-31-2009, 07:32 PM
The sights are Pedersoli Creedmoor #430 rear and the corresponding front sight. I've tried .039, .052 & .115 rear arpeture sizes and the cross hair insert in the front. Nothing seems loose in the sights.

I rest the gun about 3" back from the muzzle. The same all the time. I'm thinking that maybe my hold is the problem? Any advice on hold? Do you hold tight against the shoulder or?

There is 1 unexplained thing I've noticed. I never need to move my rear sight left/right but sometimes the next time I shoot with the same load I have to change the rear sight height. I've had to go from a .68 sight setting one time to a .71 setting next time.

I can't notice anything loose. Should I try to shoot with the forestock removed?


I have found that the crosshair front insert doesn't do as well for me as a simple circle insert. The human eye will find the exact center of the insert as well as the apertures. YMMV but it is a easy test and I cut my groups in half to 1.5" for 10 shots. Let us know what ya figure out.

SS

Don McDowell
08-31-2009, 09:36 PM
Just for kicks , maybe go to the thin post insert,use a 6 oclock hold on the bullseye. Lots of times recticles can sort mess things up , unless you have a very good contrasting aiming point.
Try resting the barrel in the sticks so the barrel is in sticks with the forearm up against the sticks.
Yes going back and forth 3 points on the sights isn't uncommon. Has a lot to do with the light .

HPT
09-01-2009, 08:12 PM
I checked and there is no gap between the forearm and the action. Could this be a problem? The rear screw tightens the wood to a mounting block and you can see that the metal & wood make contact. The front screw screws directly into the barrel. I can't tell if the wood can be put under tension by overtightening this screw, but I think so (as the wood is carved out deeper here). Should I relieve some of the wood so there is a slight gap between the forearm & action? Should I tension the front screw only until I can tell the forearm is not loose (maybe put blue loctite on threads so it doesn't loosen?).

Don McDowell
09-01-2009, 08:19 PM
Before you go to messing with the wood etc, you may want to go inside that barrel and do some lead mining. Those 457 bullets undoubtedly left lead deposits in the throat and not far from the muzzle. Once there's absolutely no chance of any lead in the bore, start the shooting over with the .459 bullets, and concentrate on you bench techique and sight picture.

RMulhern
09-01-2009, 08:31 PM
HPT

Take your forearm off....use a flat bastard file to remove just enough wood from the flat/rear portion in this area...just enough to be able to slip a thin business card betwixt metal and wood. Go to Ace Hardware to the bins where they store the thin neoprene washers that are just about the size of a dime or slightly larger with an inner hole that your forearm screws will fit through. Using a thin amount of glue on the bottom of the washers......place them inside the channel over the screw holes. Reinstall the forearm and don't 'honk' it down too snug; just enough to retain tension! Go back to the range and shoot again!

You can thank me later!!