What to make of this

[JDHasty]

Per the pic the case on the right appears to show reamer marks on the case? That would explain the hard extraction for what should be a usable load. You may have two separate issues. Even the pierced primers do not show the severely flattened primes normally associated with blanked and pierced primers due to over pressure.

Also, the firing pin indent looks to be larger than 0.062". The firing pin hole should have be sized to 0.065" for a 0.062" firing pin. This is for a Rem 700 but these sizes have worked very well for me. https://bordenrifles.com/wp-content/...g_pin_bush.pdf

Per scaling the pics the blown area appears to be about 0.090". If correct that is still BP size?

The data below is using the IMR 4198 at 14.5 grains with a 25-grain bullet.
https://loaddata.com/Metallic/MetallicPrintable?id=966

Bingo. The firing pin is .092. Gauged it with a #42 drill this morning. When I got it I was told the firing pin had been bushed. No big deal, I will send it off and have that done. I sized the cases I fired, but will fire a couple today and send them to Denis Olson.

[SSGOldfart]

Are you still using the H4198 or did you go with IMR 4198 ?

[JDHasty]

Are you still using the H4198 or did you go with IMR 4198 ?

H4198 Bought a fresh pound a couple days ago and have been using it.

[M-Tecs]

I'm also seeing some roughness on the neck from reamer marks and think that may account for the sticking. They aren't stuck all that tight, a mild tap from the rod is all it takes to free them.
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Attachment 340073

What are you going to do about the reamer marks? The case on the right show's reamer marks in the case body.

[JDHasty]

Attachment 340073

What are you going to do about the reamer marks? The case on the right show's reamer marks in the case body.

I’ve got it boxed up and sending it back to Denis. He will probably have to set the barrel back a couple threads and re cut the chamber. If he gets to it right away I’ll be close enough about mid September that I can run to Plains and pick it up. He has a Remington 580 that has been converted to 20 Garin that I need to pick up anyway.

[jonp]

From here, it looks like those two have too long of a neck.
That could cause a pressure spike, I think.


Sent from my iPhone using Tapatalk

First thing I noticed outside of the primers. Your at the max for a 25gr Hornady HP. You may have compressed the load a little due to different profiles and as you indicated you already knew, in a small cartridge a little is a lot. As pointed out the longer neck might be the problem even if you didn't compress the powder. The longer you hang onto the bullet....Did you get a velocity reading?

Gee, sure wish I had thought of that, I knew I must have overlooked something.

Stevie Wonder could see that the pressure is too high.

No need to get defensive, you came here for answers no one called you up offering advice. If you post a question like this you are going to get the obvious and the obscure to try and help you out.

[M-Tecs]

Is it a full-size Martini or is it a Cadet? Judging from the reamer marks on neck, shoulder and case body, your smith's reamer has issues? Maybe the neck and chamber can be polished out but if the barrel is going to be set back it should be at least the 0.243" neck length. That would be 4 full threads or about a 1/3 of the barrel tennon length. Depending on what type of thread relief he used the might be a problem.

[JDHasty]

I’m sending along a box of primed cases and zip loc pill bag of bullets.

I have confidence he will make it right. I’m indifferent to how much of the barrel needs to be cut off to make it right. It’s a Cadet. The fore-end is on a cantilever hanger and was bedded to 10 mil pipe wrap so it can come forward on the barrel as far as need be w/o affecting the aesthetic.

My inclination is that the reamer picked up a chip, but it doesn’t really matter so long as it doesn’t repeat. The firing pin being oversized is on me. I did not check it, I should have. I bought the action and had it shipped. When I picked it up at the FFL a guy they identified as their gunsmith was looking it over and made the remark that the firing pin had been bushed. I’ve never owned one and just assumed that he knew them and what he was talking about in that regard.

I’m an engineer and over the course of my career have cautioned others that no data is better than bad data. If you know you don’t know anything about the existing conditions then you do analysis before proceeding. In this case I proceeded under the impression that the firing pin had already been talked care of. Like I have said, it’s 100% on me.

I apologize for being short tempered earlier.

[M-Tecs]

My inclination is that the reamer picked up a chip, but it doesn’t really matter so long as it doesn’t repeat. The firing pin being oversized is on me

The lighting is not good enough to see the reamer marks on the neck for me but you noted them and I can see something there. Pictures can be deceiving but the reamer marks on the shoulder and case body appear to be more than a chip issue. Same for allowing the BP sized firing pin to go out the door. Neither of those issues should have been allowed out the door. Does the smith own the reamer or was it a rental?

Is that Dennis Olson out of Plains, Montana?

[JDHasty]

Yes, Dennis Olson in Plains. I send him work or travel across two states to do work I don't do myself. This is the first time I've ever had any issues. I believe it is his reamer, not rented. I've got a retired gunsmith buddy down in Roundup that I believe still has an old Red Elliot 17 Ackley Bee reamer that has only been used a couple times. I might follow up on that.

[Ford SD]

cci 400 are too thin of a cup for high pressure loads

[rbuck351]

I apologize if my remark sounded snarky. However, with the limited info you provided in your first post, blown primers and knocking cases out with a rod, there was only one thing I was fairly sure of, that being the load was too much for whatever the actual problem is. Have you done a chamber cast? That may or may not tell a lot but it is where I would start. I cant tell from the pictures but are those rings of protruding brass?

[JDHasty]

I apologize if my remark sounded snarky. However, with the limited info you provided in your first post, blown primers and knocking cases out with a rod, there was only one thing I was fairly sure of, that being the load was too much for whatever the actual problem is. Have you done a chamber cast? That may or may not tell a lot but it is where I would start. I cant tell from the pictures but are those rings of protruding brass?

I would like to thank everybody who has responded. It is much appreciated. I apologize to you for being flippant in responding.

I was going to do a chamber cast, I was already set up to cast the chamber on my 17 A&M Bee Stevens 44 1/2 barrel so that I can get a sizing die or die reamer ordered. I figured I had more than enough to go on w/out it and just packed the rifle up to send back.

The cases have significant evidence of some pretty wicked scoring on the chamber neck and definite roughness on the body that had been transferred to the brass case. Surprisingly it was more of a gentle nudge than a knock from the cleaning rod that broke the cases that were sticky loose. I have to plead guilty to have not seen the forest for the trees in as much as I was so focused on the pierced primer. Had I not been so obsessed with that I would have been concerned with the rest of what that case was trying to tell me.

I let the anneal on 17 & 20 Garin, 7-30 Waters and 219 DW cases run down to the shoulder and having them a bit sticky when fire forming is something I am accustomed to. Load them back up and they have always been fine.

It really is on me. I had been under the impression that information I had accepted as accurate regarding the firing pin hole having been bushed as accurate. Once I had verified that I had been 100% wrong in that regard I started looking at the machine marks on the case with more interest. I don't know how many barrels he has fitted and chambered for me over the years (a bunch), let's just say that this is not an example of his best work.

FWIW, that 17 A&M Bee barrel is going to be fun. I remember reading about the 17-caliber experimental work being done by guys in Prescott and Las Vegas back in the1960s and 70s. It doesn't swing right on either of my rifles, but I have a line on a good action and am going to probably pick it up and have the barrel fitted to it. The barrel is in fantastic shape and all evidence suggests it is a Bill Atkinson barrel. I'd like to get it going by March '26 so I can take it along on chuck and prairie dog shoots.

[JDHasty]

17 Ackley Bee data from Todd Kindler’s book Sensational Seventeens
IMG_2649.jpg

[ebb]

What the powder guy said confirmed my observations. I loaded 7mmRUM with Retumbo and 1 year latter shot some more and they were over pressure, and the temp at the first shoot was lower than the second. How do you deal with that? Shoot only ball powders?

[john.k]

All Martinis have weak extraction....coupled with a near zero taper Ackley Imp chamber which isnt perfect ........and as mentioned the firing pin/block need reducing in diameter.

[JDHasty]

Got a stubbing reamer coming that is .002 larger to deal with the neck. He is going to polish the rest of the chamber. I should hhave it back in a week or so.