Rings on tmks

[TradLife406]

When I seat my 77 tmks with my el cheapo Hornady die for the 22 creed I get a ring mark on the jacket.
I tried the eldm and the standard stem. Is this normal? They still shoot amazing just wondering if there's something I'm doing wrong.

I saw somewhere a guy said it happens with compressed loads. Which mine definitely are. But it's the only powder and charge my gun likes.

Thanks fam

 

[waspocrew]

How much of a ring are we talking? I get that on certain projectiles and haven’t given it any thought (or at least I haven’t seen any issues on target).

 

[Caseknife]

I get that a lot, but haven't worried about it at all. Chuck a bullet in a drill, coat with lapping compound and insert into the seater stem and polish off the sharp edge and contour the stem to the specific bullet.

 

[mtnbound]

When I seat my 77 tmks with my el cheapo Hornady die for the 22 creed I get a ring mark on the jacket.
I tried the eldm and the standard stem. Is this normal? They still shoot amazing just wondering if there's something I'm doing wrong.

I saw somewhere a guy said it happens with compressed loads. Which mine definitely are. But it's the only powder and charge my gun likes.

Thanks fam

After I had seen those for myself, I started doing a few more turns with my chamfer tool and made sure I got them sprayed with One-shot and since then I can’t see the marks anymore.

 

[Fireflyfishing]

I have this happen to me specifically on the 77 TMK. It can be really bad when loading new brass that has really tight neck tension.

I’ve heard of folks using bedding compound inside the stem so you have a custom stem just for that bullet. I haven’t tried this, but this is the method I would like to use. My biggest concern though is moulding the stem incorrectly and then imparting runout on every bullet you seat in the future. Another downside, you’ll need to get another stem when you change to different bullets.

I’m thinking I can get the bedding compound into the stem, put the die together and mount it up in the press. Then I’ll have a dummy case that I’ll seat a TMK into partially and let sit overnight as is. Of course everything will be covered in release agent as to not glue things together. I was planning to use jb weld and Hornady one shot to complete this project. When I have time (in short supply at the moment) I’ll give this a go.

I will say though, properly annealed once fired brass has been producing groups like this:

 

[wind gypsy]

A combination of seating force and stem geometry. Neck tension, compressed loads, and clean inside necks create seating force.

If hornady makes a VLD or ATip seating stem that’s compatible with your die, I’d use that.

 

[TradLife406]

A combination of seating force and stem geometry. Neck tension, compressed loads, and clean inside necks create seating force.

If hornady makes a VLD or ATip seating stem that’s compatible with your die, I’d use that.

The die came with two stems. I'm assuming one is an a tip/eld stem?

I'll take a picture of the ring when I get home. It's noticeable. They still shoot good so I'm guessing it's just cosmetic.

 

[wind gypsy]

The die came with two stems. I'm assuming one is an a tip/eld stem?

Maybe. Should be able to look at them and see what the contact area looks like to deduct how they'd press on the bullet.

I'll take a picture of the ring when I get home. It's noticeable. They still shoot good so I'm guessing it's just cosmetic.

It's a common thing with longer nosed bullets. I've shot a bunch this way without any obvious impacts but I dont like to if I can avoid it.

 

[TaperPin]

I chuck almost every new seating stem in a drill, wrap a little piece of fine sandpaper around a loaded bullet tip and work it in and out, moving the sand paper a little as the abrasive wears off. It doesn’t have to be perfect, you’re basically just polishing the high points off.

You can use abrasive paste, even make your own rubbing two pieces of aluminum oxide sandpaper together and mixing the abrasive that comes off with some oil or grease. Valve grinding compound works, but is fairly coarse, too coarse I think.