Pattern Variation-Bad Shell??

[BDeal]

Hi All-

I was patterning a new gun this weekend and had some strange results. The gun is a Mossberg SA 20 Tactical Turkey with Carlson .565 choke. The shell is a 3 inch 1 5/8 oz  #9 TSS. I took 3 shots at 42 yards after I zeroed at 18 yards. In the kill zone of the turkey head target I was using I had the following results:

•   50 Pellets (the shot was slightly right or it probably would have been more like 70 (I adjusted the sight slightly after)
•   14 Pellets
•   88 Pellets

I cleaned the bore between each shot with Butch's bore cleaner and ran patches to ensure the barrel was clean and dry. I have to think shot #2 with the 14 pellets was a bad shell? It looked like it may have been very light on the #of pellets (shot) that came out.

Does anyone have any thoughts here? Thank You!!

[maddog3355]

It's hard to get 2 patterns exactly the same. I know it's expensive but try again and if you get the same result I would try a less constricting choke.

[BDeal]

It's hard to get 2 patterns exactly the same. I know it's expensive but try again and if you get the same result I would try a less constricting choke.

Understood. I just don't understand the 14 pellet shot. All of the others (both at 18 and 42 yards) were decent but this shot was significantly different. It's like there wasn't enough shot in the shell.

[Marc]

A few thoughts...

If you were shooting at a 10" piece of paper it is more likely you "pulled the shot."  For that significant amount of decrease in pattern density, I would think the shot would have obviously been "rolling around" in the shell and would have been obvious while handling were it due to a short charge.

I have seen some big guys that state they "are not affected by recoil" start to pull shots BIG TIME with those stout turkey loads.

If you are shooting a large piece of patterning paper, and did not notice a short charge when handling the shell, I have no idea what happened (cause you should see that pattern somewhere on the paper).

Me...  I also pattern the gun with light/cheap target loads to see where the gun is shooting...  And finalize my patterning with turkey loads at a couple different distances to confirm it shoots a good pattern, and shoots the same spot as the lead did.

[BDeal]

The pattern was shot at a 4 foot x 3 foot piece of paper with a target taped to it. It sure appeared that there was much less shot in the one load looking at the paper. I did shoot cheap lead shot first at 18 yards to get it close. I'm a bit baffled. I will run another couple shots through it and see if anything changes.

[Marc]

Seems like a lot of varitiation between shots with no consistency (3 shots with very different densities)?

Have you been able to find the center of your pattern for each shot?  Is the center of the pattern moving, or is it stable from shot to shot?

The target is not generally the center of the pattern.  Look for the center of the most dense part of your pattern, and forget the target center when looking for the center of your pattern.

[runngun]

If it was that bad, you should have been able to feel the weight difference between the shells. I have never experienced anything like that. I have set up a lot of guns!!!

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[BDeal]

If it was that bad, you should have been able to feel the weight difference between the shells. I have never experienced anything like that. I have set up a lot of guns!!!

Sent from my SM-S908U using Tapatalk

I have done a lot of experimenting over the years with different chokes, loads, and guns and have never seen anything like this either. I'm quite baffled. Hence my post here.

[runngun]

Well hopefully you can get it figured out. Please keep us posted on the progress. Have a good one and May God bless!

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[novashooter]

It has been my experience loading my own ammo, that huge variations such as that are almost always due to wad failure. There is likely a wad out there that looks like mangled space debris, and it's probably the bad shot. I don't know a lot about TSS, but those numbers wouldn't even be good for 1 5/8oz of #6 lead, even 88 pellets is pretty bad. I would go back to the drawing board entirely on that load. Definitely change wads. Possibly use a slower/lower pressure powder and or charge. You should be looking at 200+ pellets in a 10" circle at 42 yards with TSS. Maybe try a full choke to rule out any issues you have with a the very tight choke blowing the pattern, although I've found "blown patterns" to be pretty rare.

[BDeal]

It has been my experience loading my own ammo, that huge variations such as that are almost always due to wad failure. There is likely a wad out there that looks like mangled space debris, and it's probably the bad shot. I don't know a lot about TSS, but those numbers wouldn't even be good for 1 5/8oz of #6 lead, even 88 pellets is pretty bad. I would go back to the drawing board entirely on that load. Definitely change wads. Possibly use a slower/lower pressure powder and or charge. You should be looking at 200+ pellets in a 10" circle at 42 yards with TSS. Maybe try a full choke to rule out any issues you have with a the very tight choke blowing the pattern, although I've found "blown patterns" to be pretty rare.

The pellet counts given were in the kill zone (head and neck) of the target I was using. I didn't count pellets in a 10 in circle or the numbers would have been much higher. I'm still baffled as to why the one shot was so messed up.

[BDeal]

Well hopefully you can get it figured out. Please keep us posted on the progress. Have a good one and May God bless!

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Thank You!

[deadbuck]

Were you shooting factory TSS or handloads? The only time I ever got a crappy pattern from TSS was when I forgot to slit the wads on a 20 ga load I was loading. The patterns were about 50% of what they were when I slit the wad. Didnt realize my mistake until I picked a wad up off the ground and looked at it.

[BDeal]

Were you shooting factory TSS or handloads? The only time I ever got a crappy pattern from TSS was when I forgot to slit the wads on a 20 ga load I was loading. The patterns were about 50% of what they were when I slit the wad. Didnt realize my mistake until I picked a wad up off the ground and looked at it.

Factory TSS