Lesson learned

[MontanaRifleman]

Yesterday I went to the range with a friend to do some shooting. I took my 41 Redhawk and he took his new S&W M29 44.

I also took my S&W M1500 7mm RM (Howa action) to fire some old loads I was shooting out of my Ruger M77 which is out of action at the present. The cartridges were max loads seated to fit just off the lands of the M77 and whem chambered into the M1500, they jammed into the lands about .05 I decided to reseat the bullets about .075 deeper to avoid any pressure issues, which I did. While pulling the handle down, it felt like it was camming over which I didn't think anything of. I did this with three different loads, Nosler 160 Partitions, Nosler 175 Partitons and Nosler 150 BT's.

Well, we get out to the range and I start with the 175's to see how they group. The intent being to check out the accuracy of this rifle as my back up for spring bear season. Some of the 175's seem to be chamber ing a little difficult but ididn't pay much attention to it. I got fairly good results, sub MOA for 3 shots and opened up a little after. Then I tried the 150 BT's just for grins and not a hunting load. I could not get them to chamber and thought what is going on here??? My friend looked over the rifle and cylced the bolt with no cartridge a couple of times and tried to feel for an obstruction in the chamber. Then I looked at the cartridges. Yep, the cases had wrinkled in the shoulder just below the junction of the neck. I then checked the 160's and they looked OK except for a slight buldge in the neck (the necks were turned on all these cases) just below the mouth rim. I tried chambering one and it went in. But not smoothly. I felt safe firing it, so I did along with two more. They fired a 1" almost verticle group.

These rounds were anywhere fom 14 - 10 years old. the different bullets were loaded using differen brass - Win, Rem and Fed. Oddly enough the Fed cases (the 175's) showed the least deformation with just a slight bulge in the neck, followed by the Rem's with a slightbulge in the neck and a slight wrinkle buldge in the case wall where it meets the shoulder. The Win's wrinkled badly in the shoulder just below the neck.

Anyway, the next time I will be much more careful about reseating bullets (if I ever do again), to examine each one very closely. I probably could have used a kinetic bullet puller to the loosen the bullets from the neck first. And no, they were not crimmped.

Thought I would pass along.

-Mark

[Smitty of the North]

Ain't that a Revoltin Development

MR:

So, your conclusion is that the bullets were frozen in the necks, and when you re-seated them, the necks were pushed down wrinkling the cases.

AND, the die wasn't adjusted to crimp.

I'm sure you know that 2 different rifles don't necessarily have the same size chambers.

You're sure that they weren't just a little long at the neck-shoulder junction for the chamber??? I ask only because it seems strange that the bullets would be that tight,

Granted, a neck-turned case would have a thinner neck, but why would that effect the shoulder? All I know about neck-turned cases is 2nd hand from a 1K BR type, but I speculate the necks could have been turned too far, so that the pressure on the bullet caused the wrinkles, and would anyway, whether the ammo was old or not.

Smitty of the North

[MontanaRifleman]

Smitty,
Yep, I think the bullets froze to the neck over time. I turned the necks way back when in search of accuracy (another discussion) and I'm sure that would weaken them a little. But interestingly, I'm looking at a couple of the Rem cartridegs and one is slightly buldged in the neck and the other is winkled in the shoulder and not buldged in the neck.

And yeah the two chambers were different sizes, in length to the lands, or maybe I should say the throats were different sizes? which is why I reseated them in the first place. But I'm sure that had nothing to do with deforming the cases because I checkd them all after discovering the problem and they were all deformed to some extent befroe I attempted to chamber them. Also the SAAMI spec on the 7mm max length is 2.5 and the fired cases are about 2.47

MR

[Smitty of the North]

Recently, I had to seat the bullets of some loaded ammo deeper too. (I had a new and longer barrel installed on my 280) The sized cases fit the new chamber fine, but the distance to the lands was less.

Their were no issues. They weren't old loads, though.

Smitty of the North