Loading Nosler 100 grain BTSP in .257 Roberts

[Reloader2025]

It is a shirt action.

 

[Reloader2025]

short action.

 

[Reloader2025]

This rifle actually belongs to my son and it has the short action. I gave him a couple boxes of the old Nosler 100 grain BTSP and he immediately ran in to the issue at hand and called me for advice on loading these bullets as they kept falling back into the case after crimping with his RCBS 3rd stage crimp die. I suggested moving the bullet beyond the stated maximum OAL but a modest 0.002 increase in OAL and the cartridge would not chamber. Therefore, I thought about asking you fine gentlemen for your suggestions and I can see that was the correct solution! I agree that a flat base bullet would be the solution for this particular rifle. I ordered a Lee Factory Crimp Die for his future hunting loads but I do not think crimping too far up the olgive is a good idea. Thank you all for your advise on this problem.

 

[JD338]

Thanks for confirming that the rifle is a short action. As Guy mentioned, run the 100 gr PT and you should be able to crimp.
As a side note, I only crimp 44 Rem Mag and 45/70. All other cartridges, including 338 RUM, 375 HH Mag and even the 416 Wby Mag, do not get crimped and I have never had any issues.
We are glad you are here and the members here were able to offer their knowledge to assist you.

JD338

 

[PJGunner]

Hey Paul, is it possible to remove the block in the magazine well then use a longer follower so it will accommodate the longer cartridge length?

You might be able to as I think it's just tack welded in place. I know you have to replace the ejector and maybe something else but I forget what. I called the parts places and they always seem to be out of stock on those particular parts. Must be a lot of people doing that conversion. The easiest way is just replace the magazine pox and ejector from what I understand.
Paul B.

 

[Guy Miner]

I gave him a couple boxes of the old Nosler 100 grain BTSP and he immediately ran in to the issue at hand and called me for advice on loading these bullets as they kept falling back into the case after crimping with his RCBS 3rd stage crimp die. I suggested moving the bullet beyond the stated maximum OAL but a modest 0.002 increase in OAL and the cartridge would not chamber. .... I ordered a Lee Factory Crimp Die for his future hunting loads but I do not think crimping too far up the olgive is a good idea. Thank you all for your advise on this problem.

I just saw that - the part in bold attracted my attention.

Neck tension alone should grasp the bullet firmly, even without a crimp.

I think something is wrong with the neck sizing. It's not tight enough. Could be a die issue or it could be a brass issue...

Try adjusting the die, and perhaps try a different brand of brass. Are these factory 257 Roberts cases or are they made from something else?

Worth a thought.

Regards, Guy

 

[RL338]

I found that in so doing, the slightest bump and the bullet falls back into the case due to insufficient crimp.

What brand of dies are you using?
Just a guess would you be using a Lee Collet die and work harden brass that is leaving you with next to no neck tension.

 

[Reloader2025]

Gosh, I responded to RL338, but I don't see my response here so I'll try again. The brass used in this post is new Hornady brass. I also gave my son a healthy supply of once-fired Winchester and Remington brass, all of which he properly trimmed to minimum OAL (of the brass). My son is very meticulous and his hand loads are exceptional, just like he was taught. He is using a 2-stage RCBS die set with a dial caliper to gage factory specifications, including loaded cartridge OAL, as detailed by the Lyman 48th Edition reloading manual. I suppose there could be a problem with the Stage-1, RCBS primary recapping and resizing die, but I think that would be unlikely since a bullet that has been seated too far beyond the bearing surface area (including cannelure), past the shoulder and onto the olgive surface, would most likely have little, if any, friction contact remaining between the bearing surface of the bullet and the inner surface of the cartridge neck. In this case, the old Nosler 100 grain bullet also has a boat tail base, which also reduces the length of the bullet's bearing surface, thus allowing a bullet to fall back into the cartridge interior if jarred or bumped in any manner which, I suspect is what has happened here.

 

[RL338]

The brass used in this post is new Hornady brass.

Was this new brass sized before loading? New brass should hold a bullet with decent neck tension.
Have you check the diameter of the suspect bullets to see if they might be undersized?

 

[Guy Miner]

Gosh, I responded to RL338, but I don't see my response here so I'll try again. The brass used in this post is new Hornady brass. I also gave my son a healthy supply of once-fired Winchester and Remington brass, all of which he properly trimmed to minimum OAL (of the brass). My son is very meticulous and his hand loads are exceptional, just like he was taught. He is using a 2-stage RCBS die set with a dial caliper to gage factory specifications, including loaded cartridge OAL, as detailed by the Lyman 48th Edition reloading manual. I suppose there could be a problem with the Stage-1, RCBS primary recapping and resizing die, but I think that would be unlikely since a bullet that has been seated too far beyond the bearing surface area (including cannelure), past the shoulder and onto the olgive surface, would most likely have little, if any, friction contact remaining between the bearing surface of the bullet and the inner surface of the cartridge neck. In this case, the old Nosler 100 grain bullet also has a boat tail base, which also reduces the length of the bullet's bearing surface, thus allowing a bullet to fall back into the cartridge interior if jarred or bumped in any manner which, I suspect is what has happened here.

Something is absolutely wrong with the neck sizing. It's either the brass or the dies.

There should be sufficient neck tension to hold the bullet securely.

Perhaps try a flat base 85-100 grain .257" bullet?

Guy

 

[Guy Miner]

I have a very old late 40's or early 50's rifle that was chambered in 257 Weatherby early on before there was brass or ammo available for it.

In those days 300 H&H brass had to be shortened, necked down and blown out. I have the dies for that and some ammo that my grandfather made with those dies back in the 1950's. The old dies work great with resized 300 H&H brass. They don't work worth a hoot with modern 257 Weatherby brass! They are made for the thicker necks of the resized 300 H&H cases. I got new dies just to use with new brass. Proper brass.

I suspect you've got something like that going on... The case neck isn't getting sized down quite enough. Close but no cigar.

Are you full-length resizing? Is the case mouth being resized?

Just asking... Trying to help.

Regards, Guy