Over pressure?

[dave-t.]

I have noticed an ejector mark on my .257 R brass. The load is 47grn/RL19 117grn spbt Horndy, Frontier/Hornady brass, once fired (recovered factory loaded brass). I get the same mark on the brass loading down to 44grn. COAL is 2.780".

Hornady book lists 47.2 of RL 19 as max load, 2900fps. Most other manufactureres info list 43.5-44grn as max with RL 19 (2740-2800fps).

Primer pockets are still tight, extraction is no problem, primers are somewhat flattened, but not bulging or spread over the whole primer pocket.

I have shot Hornady factory loads with the same bullet 117grn, at a listed velocity of 2780fps, with no bright spot on the case head.

I'd like to get this bullet to shoot, in fact it shoots very well in the factory loads and my handloads with some 3-shot groups in the .27"-.6" range, but I'd like to keep my rifle and face intact as well.

Is 3 grns under max book info still too hot? Is there an issue with my bolt face? Should I try diffferent powder to achieve 2750-2800+fps with this bullet? Should I just drop to the 100grn bullet weight, and start over to get a trajectory that I'd like with this rifle/cartridge?

To muddy the waters a bit, I get the same bright ejector mark on my downloaded ammo, 90grn Sierra, with 9 grns of RedDot, brand new winchester brass neck sized, at around 1700-1800fps.

I have never had that bright mark on any of the 3 different factory loads that I've shot from this rifle, Rem, Win, and Hornady. I'm confused.

[bill m]

I wonder if a full neck size might be a good test? I'm thinking that you have made sure that there is no build-up of fouling or other dirt build-up in the breech? The ejector doesn't have anything about it that could cause a "grab" of the brass?
All you can do is try to eliminate everything you can.
The max loads are often not the same from Hornady to Sierra to Lyman, etc.... We often only look at the powder as the defining element. But brass, bullet, and primer manufacturers also play a roll in the final velocities and pressures. I don't often use everything that the manual states. That's why they always recommend that we approach maximums cautiously.

It will be interesting to hear what you discover when this is all over.

[dave-t.]

I have posted on another site, and didn't get any definitive answers yet. Some say if you only get one sign of pressure, and no others, than you are fine, others say change powder, others say look at the bolt face/ejector. No one thought I was about to detonate, thank God.

I am unsure and don't have the experiennce to have a solid lead really, but want to ensure that I have a load that is safe first, and that gives me the accuracy and velocity that I am hoping for...1" or so at around 2800fps +/-.

[dave-t.]

I whipped up a round last night 43grn RL19, with the 117grn bullet and after firing it, it had no ejector mark on the brass, very round primer, and all around looked like fired factory brass. If the book is right, that is 2600's fps. I just think my rifle doesn't get along with RL19 up to the velocity where I want it.

I'm going to track down some IMR-4350 and start again.

4350 is the powder that I wanted to use originally, but it has been sold out more often than it has been available around here. I'll make it my mission for the weekend to get some.

[Shipster]

dave-t I have a 280 Rem that I have been loading for many years and I had ordered some new Remington brass to start replacing the old Remington brass and I noticed the same ejector marks on the new brass your experiencing but not on my older brass, same load, same everything except the brass. My summation was softer brass. Ordered another 100 rounds of Remington brass from a different distributor and back to no ejector marks. Were the once fired brass you were using fired in your rifle or another rifle?

Shipster

[Alan R McDaniel Jr]

Dave, from the info you've provided, I don't think the marks are being caused by over pressure loads (probably). As Shipster said, perhaps the brass is the culprit. The whole pressure thing is a huge variable in itself in that the book gives a pressure reading for the load based on some very controlled situations. Max pressure in your gun is probably different than in mine, but you knew that already.

The thing to do is exactly what you're doing. Proceed with caution to maximum listed loadings, and watch for signs of excessive pressure. Back off when you get there.

If reloading was about just dumping some black stuff in a case and topping it off with a chunk of lead, it wouldn't be any fun, and any yahoo could do it.

Keep the faith, be safe.

Alan

[dave-t.]

The Frontier/Hornady brass with the marks was shot through my rifle originally with/from factory loads.

The max for other bullet manufacturer's with RL19 is 43-44grns. My brass quit getting marked at 43grn.

I started by fully cleaning the rifle with a copper remover and gun solvent just to remove any fouling as a posible problem.

I did find some IMR4350, and worked up loads with it, starting at 38grns, and worked up to 42.5 (book max 42.6grn) with no pressure signs at all. I had too much else going on this weekend to get beyond shooting into the backstop to check pressure. My plan is to work up loads for accuracy, focusing my efforts between 41-42grns, which is back at my target velocity 2800-2870fps or so with the hornady 117grn bullet.

The original handload with near max charge of RL19 was fantastically accurate, very close to .5 moa, but is out of my my comfort level considering the remote possibility of an over pressure situation. I'll live happy if I can get close to 1 moa with IMR-4350 and no worries about brass or pressure.


While I was at it I ran through the listed charges of H-380 and Sierra 90grn hpbt to set the safe max in my rifle (41.5-45.5grns) with no problems at all.

[bill m]

So was there just a brass problem?

[dave-t.]

Thanks for the comments fella's.

I did my last testing with new Winchester neck sized brass.

If I had to make a guess I would say my rifle or the Fontier brass just doesn't like RL 19. 43grn is where the Frontier brass quit getting marked. I haven't shot the RL 19 with 117grn hornady in the Win brass, and that powder is off the table as an option right now. I can't tell what the problem is exactly, and don't care to follow up on it as long as I can find accuracy with a different powder.



RL19 has been great for accuracy in my 300wm, 71.5grns with a 180grn Hornady, producing .8" 3 shot groups at 100yrds at what should be around 2970fps. I'll just keep the RL19 to the 300wm.