# Erratic bullet groups



## silentstalker (Feb 19, 2008)

I am getting very erratic results from my CVA Kodiak .50 cal. In the past I shot 338 gr. powerbelts and 300 gr. SST with what I thought was pretty good accuracy but with a 1x how could you really be sure.

Last year I switched to 300 gr. Scorpion PT bullet over 90 gr. BH 209 with a W209 primer. Again, I managed a couple 2" groups with the 1x. I never shot either load a ton just sight in and then a handful of field shots.

This year I bought a 4-12 scope and now that I can see the target really well off a secure bench rest, my groups are in the 8" range with an occasional 3-4" group.

I have shot 300 gr. Barnes mz, 300 gr. Scorpion PT, and recently the 260 gr. Nosler PT with a black harvester sabot. They have all been shot with BH 209.

I have picked up a few used sabots recently and this is what they look like.

My question is this, are they telling me anything with the bulged out bases and the one petal pulled back. Could this be why my groups are so bad?


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## Buzzard (Oct 20, 2008)

I'll give you some ideas the have affected accuracy for me over the years. Number one problem for me is the barrel heating up. A warm or hot barrel has really opened up patterns for me. Sabots and Power Belts are both subject to this problem. Using a aligning tip on the end of your ramrod can make a big difference on some muzzy's. The scope could be the issue as well. 

Also, the petal on the second to last picture looks twisted me. I got a small ding near the crown on a muzzleloader and one petal would twist and stretch as I started the bullet. The accuracy went into the toilet on that rifle.

I personally have had better accuracy with MMP sabots.

Good Luck, Brad


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## silentstalker (Feb 19, 2008)

Thanks for the input. I actually was swabbing and letting the barrel cool real good between shots. 

I have had the bases and rings as well as the scope evaluated by a gun guy. Everything appears good. 

Im leaning towards a pressure issue especially with the BH 209 and the harvester sabots not getting a great seal. I am going to try some MMP sabots, the HPH-12 are super tight so I may try the -24 depending on which bullet I am trying to shoot.

Any other ideas or thoughts?


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## CPAjeff (Dec 20, 2014)

Quick question on BH209 - are you using 90 grains by weight or volume?


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## muddydogs (Oct 7, 2007)

Have you worked with you powder charge? I would try moving up in 5 grain increments and see if that helps the groups. Might also be weak ignition, W209 primers work well in one of my muzzys but a hotter primer is recommended for BH209. In my main hunting muzzy I use CCI 209M's.


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## silentstalker (Feb 19, 2008)

CPAjeff said:


> Quick question on BH209 - are you using 90 grains by weight or volume?


I am using 90 gr. By volume.

As for the W209 primer I Have never had a misfire with it, does that mean it's getting the job done or should I get some cci primers?


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## CPAjeff (Dec 20, 2014)

I found that my accuracy increased dramatically when I switched to the CCI 209M's from the W209 and when I increased the powder charge. 70-75 by weight (100-107 by volume) was the "sweet spot" for me.


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## silentstalker (Feb 19, 2008)

I will go pick up some CCI primers. Maybe that will improve things. I actually have tried everywhere from 90-120 gr. By volume with the W209. Nothing has been consistent except inconsistency!


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## Buzzard (Oct 20, 2008)

Try shooting without swabbing the bore between shots. Don't include the first shot in your group. Just make sure the flash hole on the breach plug is clear. Leaving even a small amount of solvent based bore cleaner can really effect accuracy.

Another option is to run a patch with acetone after swabbing the bore. Then dry patch. It may make loading more difficult. Then you know the oil residue is out.

The SpinJag Bullet loader is the best aligning tip I've found. They run about $20. 
http://www.spinjag.com/spinjag_loader.php


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## DallanC (Jan 13, 2009)

I honestly cannot figure how anyone could miss-align a proper sabot/bullet. Unless you are shooting a super light weight bullet (160-180gr) with a really low SD, the surface area on the sides of the bullet are so long you can't get it ****eyed. The sides of the barrel uniformly press on it and force it straight.

I challenge people to TRY and miss-align a bullet in a sabot (assuming of course you are matching bullet diameters with the proper sabot size for that diameter).

What "aligners" can do, is apply even pressure to the bullets tip, minimizing deformation. That really only applies to softer, lead nosed bullets though. 

Its great marketing people believe they have to align their bullets with the special tool.

As for the OP, try some different brand sabots too. I love the green Hornady sabots, they open up like 4 petaled flowers virtually every time. Looking at the above (are those crush rib sabots?) I don't see much engaging of the petals to rifling... it s not leaving much of a mark for sure, maybe an indicator of a poor fit?. 

Also, make sure your fingers are dry when you insert the bullets into sabots, you want the bullet to disengage as quickly and evenly as possible. Any stickyness between the bullet and sabot is bad mojo.

-DallanC


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## silentstalker (Feb 19, 2008)

Yeah Dallin, they are crushed rib sabots. I have some mmp that I thought were too tight but maybe they will be better. There is virtually no marks at all on the petals. That could be causing my bullets to not spin properly and also give be pressure issues which all could be consistency issues?

Also I am sure its not an alignment issue. Although a "loose" sabot could cause it to wobble maybe?

Makes sense, I just hope it works. If not I am about ready to buy a new gun.


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## Buzzard (Oct 20, 2008)

Dallan, Back in the early 90's Barnes was working on their original MZ bullet. They were struggling to get acceptable accuracy. I went down and worked with them. At the time the only sabots had a short petals on them. Del Ramsey(owner of MMP) suggested a bullet aligning tip, made to fit the ojive of the bullet. Barnes made one to fit their bullet and the accuracy issue was solved. Next Barnes had MMP build them a longer sabot that accomplished the same thing. The trade off was increased loading effort because of a larger bearing surface. I still often use the shorter sabots with longer bullets. I can use a tighter sabot and still get it down the bore. 

It might be possible that the crush-rib sabot would allow the bullet to get ****-eyed by crushing the ribs uneven. A bullet aligning tool would minimize this possibility.

In addition, the SpinJag greatly reduces loading effort by taking away the friction from the ramrod/bullet contact. I've had issues with the aligning tip unscrewing while loading. The SpinJag solved this problem. My guess is if you try one you'll like it.


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## El Matador (Dec 21, 2007)

Sabots could be the problem. I've had best luck with a tight-fitting sabot and swabbing between shots, although with BH powder you shouldn't need to swab.

I was getting excellent accuracy out of my Omega (sub-MOA) when all of a sudden things went to crap. I was getting major fliers once every 2-3 shots. I thought it was the scope so I replaced it...no change. The bore looked clean and bright. Somebody said it might be plastic fouling due to the sabots but I was very skeptical of that. I decided to try scrubbing the bore like crazy with a plastic solvent bore cleaner just to eliminate that possibility. Well, it solved the problem. My gun went right back to shooting tiny groups.


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## DallanC (Jan 13, 2009)

Yes I've had plastic fouling issues as well. My tightest groups in my Rem come from a clean bore with the ever so slightest film of bore butter inside. That slight film reduces friction which in turn reduces heat which in turn reduces plastic build up.

I'm lucky though when it comes to the "best load", Remington came out and admitted they designed the entire 700ML around 240gr XTPs in Hornady (Green) sabots, over 90-110grns of Pyrodex powder. That load has been nothing but outstanding for me, no variation has come close.

-DallanC


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## silentstalker (Feb 19, 2008)

So it seems to me like my problem is either improper bullet fit, plastic fouling buildup or both.

Can the plastic buildup be seen with the naked eye or how do you tell? Which cleaner do you recommend?

I have Hornady red low drag, harvester crush rib, MMP HPH 12 and 24, and Buzzard has offered me some MMP 3 petal sabots to try.

I will be shooting Wednesday and hope to see some improvement by then! Thanks for all the recommendations and help!


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## DallanC (Jan 13, 2009)

Use a bronze brush to remove plastic fouling. Any cleaner you want with that.


-DallanC


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## silentstalker (Feb 19, 2008)

Ok. I have the bronze brush. I will scrub it good before I go out.


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## silentstalker (Feb 19, 2008)

I stepped up to the MMP HPH -12 and now I have petals ripping off. Does that mean too much powder/too tight?


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## DallanC (Jan 13, 2009)

Probably. Just like with centerfire reloading, start with a light load to make sure thats ok, then work up. You need a baseline to measure performance against. Try 80grns of powder out of a clean barrel. 


-DallanC


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## silentstalker (Feb 19, 2008)

So I am shooting BH 209 with firm instructions that they should not swab between shots. I continued on with shooting trying different bullets and sabots combinations. Here are some pics of the results to maybe help you guys help me!




























It seems my gun favors the scorpion PT 300 gr. In an MMP HPH -12 sabot, And Nosler PT 260 gr. In an MMP HPH -24. Both with 90 gr. BH 209. They show potential with shots 1/2 hitting in a nice tight group.


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## silentstalker (Feb 19, 2008)

Question is, what are the reasons behind my flyers after printing the first two shots so closely together? I am stumped. I am still getting a petal coming off every once in a while at 90 gr. But not like they were at 100 and 110. It was almost every shot with the higher charges.


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## justismi28 (Aug 19, 2014)

So this may have already been addressed, and I know I'm late to the party. But are you shooting the Barnes TMZ or the TEZ? You said it was the MZ so I assume it is the TMZ? If that is the case, and you are shooting the boattail out of the black crushed rib (or even the mmp) this could be the cause of your problems. It would also help explain the poor performance of the first sabots posted.

If that is the case, maybe look at the Yellow Crushed Rib? They are made for a boattail.


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## silentstalker (Feb 19, 2008)

Yes, I am shooting the barnes expander mz with the provided mmp hph -12 sabot. I have also tried the mmp hph -24 sabot. Both are designed for the flat base expander mz as far as I know.

An update: i tore the scope off last night and am having the scope checked and buying better bases.


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## justismi28 (Aug 19, 2014)

Ok, I was thinking you meant the TMZ (which is a boattail version of the TEZ). The expander mz is a different bullet with a flat base. That clears that up and we can disregard my last comment.


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## silentstalker (Feb 19, 2008)

No worries, i appreciate all the feedback. 

It looks like my scope may be bad. With my current rings and scope on an accurate rifle its all over the place. We have progress and I can pull my muzzy out of the dumpster... Lol.


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