Shot some (100 rounds) yesterday and was inspecting the primers after cleaning the rifle last night. These show the Federal 210M primers after igniting 23.6 grains of IMR 4198 pushing a Hornady #3060 bullet (170 grain flat-nose) out of one of my 1970's era Winchester 94s. Looks to me like the beginnings of cratering but I am new to the diagnostics of all of this. Your opinions please. I'm not stuck on the above load, and it's by no means a maximum in the loading manuals.

Shot some (100 rounds) yesterday and was inspecting the primers after cleaning the rifle last night. These show the Federal 210M primers after igniting 23.6 grains of IMR 4198 pushing a Hornady #3060 bullet (170 grain flat-nose) out of one of my 1970's era Winchester 94s. Looks to me like the beginnings of cratering but I am new to the diagnostics of all of this. Your opinions please. I'm not stuck on the above load, and it's by no means a maximum in the loading manuals.


Let-ca It looks to me as well as the beginning of cratering. I checked the IMR web site and the load you quote is the max IMR recommends for a 30/30 pushing a 170 gr slug. I would back the load off a bit and try again. I recommend you check the IMR web site. I think you made a good call in questioning what you see. Be Safe KGS

Let,

I believe the 30-30 is a low pressure round and you can exceed max pressures before you see the signs. Good catch.

Dave :cool:

The outside edge of your primers are still round, so pressure isn't very high, by .30-06 standards. Of course, .30-30 max pressure is much lower and I agree that you'll be over max before you see the signs. I also note that my Hornady, Lyman, Sierra and Speer manuals don't have a recommendation for 4198, which should tell you something. The cratering, which I can't really see in your picture, may be due to an oversized firing pin hole.

I can't say if you're getting into dangerous territory or not. What do the primers look like in your other 94s? A chronograph would be real handy here.

Bye
Jack

Check the IMR website as kgs did. I think he's on to something. It does look like the start of cratering but may be due to the softness of the primer cup since the edges are still round. Best choice on what to do should start after checking that website.

I'll try dropping it down a grain or so and take another look. I shot 60 rounds of this load on Saturday and all of them looked pretty much like the photo.

My primary interest is accuracy, rather than speed so backing off isn't an issue. Thanks to all - And, yes I was incorrect; this is the max load on the IMR table. I surprised myself because I generally don't ever load max loads. Don't know what I was thinking. (Sad thing is that this was a fairly accurate load. See photos of targets below:

50 yards with open sights:

http://shootersforum.com/attachment.htm?attachmentid=4324
http://shootersforum.com/attachment.htm?attachmentid=4325
http://shootersforum.com/attachment.htm?attachmentid=4326

Looks to me like normal primers. If it were starting to crater you would see a rim form around the impression the firing pin made. Your's look to be smooth. Thats what I see from the pic anyway. I don't see a problem with them.

You were at full grain under IMR spec. How is the Bolt? http://www.imrpowder.com/data/rifle/3030win.php
What brass?

You are well under max in two of my old books, but my three newest books don't even list 4198 for the 30-30. Maybe a little too fast buring for that cartridge with todays powders.

Shot some (100 rounds) yesterday and was inspecting the primers after cleaning the rifle last night. These show the Federal 210M primers after igniting 23.6 grains of IMR 4198 pushing a Hornady #3060 bullet (170 grain flat-nose) out of one of my 1970's era Winchester 94s. Looks to me like the beginnings of cratering but I am new to the diagnostics of all of this. Your opinions please. I'm not stuck on the above load, and it's by no means a maximum in the loading manuals.

"Modern Reloading 2nd Ed" lists 23.6gr of IMR 4198 as the "never exceed" for .30-30 Win and 40k PSI, which is pretty hot, and Federal primers have a reputation for being hotter than CCI or Win primers, so if that load was worked up with those primers instead of Federal (and I suspect it might be), then that load could be leaning towards the over pressure side.

I see this as a low preasure event. Looks like the primers are backing out of the pockets? Cases are gripping chamber walls, but are not stretching back to reach the boltface?
Perhaps a headspace issue or too much sizing?

I would try a factory load or two to compare it with!
Cheezywan

I went back to the reference manual I used, Complete Reloading Manual for the 30-30, under the IMR powder section. It lists IMR 4198 powder at 24.5 grains pushing a 170 grain REM bullet using a Remington 9 1/2 primer. So, that's where I got my info, thinking that 23.6 grains would be a safe place to start since I was using a Federal 210M primer.

I'll back off a bit and see if they look any different after the next session.

I've always thought of IMR4198 as a very touchy powder. I have several small calibers that I use at the range and use IMR4198, like .222Rem. and .222Rem.Mag. When you get up around max charges cratering is quite common. This is indeed a temperamental powder, but one noted for fine accuracy. Best wishes.

Cal - Montreal

I had a problem once with a .223 cratering primers and found that the problem was the brass was over length causing higher pressures.

I keep going back and looking at your picture. No really appearant case head burnishing, primers do not look flattened. Id want to see a bunch of your other fired cartridges to get more insight. I was thinking along the same lines as Jack.

What kind of shape is your firing pin in?
How much wear and does it closely match the hole in the bolt face in size?
If the hole is overly large, you can have what looks like cratering without other signs of pressure, like sticky bolt throw/ hard eject, burnished case heads, flattened primers, etc.

I know, Im not much help. I'd go back and look at a lot of the other brass you have fired recently in it for more signs.

I'm putting together some new loads tonight. I'll put five of the last load in and them some with reduced charges.
The gun is fairly new to me and I haven't taken the opportunity to examine primers from previous outings. I really appreciate all the good advice given here. I'll also check out the firing pin tonight and see if I can see any abnormalities.

You have to be very careful with these powders that are intended mainly for small capacity bechrest type calibers, powders like IMR4198 and Rel-7. You only have to exceed maxium by a tenth or two to get into trouble with split necks and cratered primer pockets. Too light a load will also cause probles here. I also have had heartaches with them. Best wishes.

Cal - Montreal