Anyone have load recipe for fire forming 264 Win Mag with faster powder?

[Jurome]

Hello everyone,

I have a 264 Win Mag in Model 70 I purchased last summer, which came with a whole bunch of new unfired brass, factory ammunition and previous owner's hand loads.

Looking for safe recipe for firing a 140 grain Sierra SBT to fire form new Winchester brass.
Last fall I was noticing a trend of mis-fires in some of the loads with new brass which bothered me (thinking it was the rifle), until I found the problem. Dang Winchester brass (new unfired) is SO SHORT. Yes belted magnums use the belt for headspace on first fire, but these shoulders are 0.030" over sized from the factory and some of the rounds simply push forward in the chamber when firing pin goes forward and no bang. I have 100% success with all factory ammo and all my re-loads that I bump the shoulders a couple thou work flawlessly. The only mis-fires occur with new, unfired virgin brass, seating the bullet to some sort of jump. To get them to fire I have to seat the bullets to touch the lands to prevent the cartridge moving forward. Seems to work well.

I have successfully been fire forming these cases with my 264 powders (Retumbo, Magnum etc), but got to thinking if it would be easier to not waste valuable powder that I like to use for my good ammo?

I have a ton of other powders I am not using at the moment which are a little faster. I see there are some loads for IMR4350 but I don't want to waste that powder either as it is in short supply for me. I have Superformance on hand I could use but I cannot find any data anywhere and I don't belive Quickload has anything on it either. Google AI hit gave me an IMR 4064 suggestion and one for Superformance but I don't know the source.

I am using economical bullets to load with and would like to do the same with my powders...especially those powders I am not using much of these days. Only have about 75-100 brass to go then I should be done with this program.

Thoughts on this?

 

[Jurome]

whoops!!!...never mind lol, I looked everywhere on the internet except...the Nosler load data assuming it would not be in there lol. Apparentlly it is 47.0 - 51.0 grains of IMR4064. That is embarrassing, sorry about that. I just assumed there wouldn't be a load with a really fast powder, for a heavy bullet...for a magnum. Weird.
Further research on the net found a very old reference for a 50 yard competion load which mentioned 47.1 grains, surprisingly similar.

IMR4064 will be perfect for forming! I have lots of it and am not using it much these days...these loads are not so much about power or accuracy. I just need to puff up the cases to a realistic and usable dimension. Dang, all this trouble I should have bought myself a 280 Ackley instead. But I do love my .264 Win Mag tremendously with that beauty long barrel, it's the only rifle I own that meets or exceeds muzzle velocity data out of the loading manuals when I develop loads...I have a thing for all the older classics.

 

[jimbires]

on a belted case , the shoulder length means nothing for correct firing . the belt holds the brass case back against the bolt face . the belt sets the headspace on the initial firing . after the brass is fully formed , the brass can be resized to headspace off the shoulder . most new brass takes more than one firing to get fully expanded .
Peterson brass , now sells what they call long brass , for a few belted cases . the long brass is much closer to chamber dimension .

https://petersoncartridge.com/blog/peterson-cartridge-introduces-300-win-mag-long

the best way to work with new belted cases , is to form a false shoulder . this will help extend case life by making the shoulder blow forward , instead of stretching the case in front of the belt . here is a link on forming a false shoulder .

forming a false shoulder

all this false shoulder talk got my interest up , I had to do it . I wasn't sure if it would be worth the effort . I found there is nothing to this .if you have the means do it , it can only help case life . I doubt I have I have 15 minutes in getting things measured , until I had 5 pieces...

forum.nosler.com

 

[SJB358]

on a belted case , the shoulder length means nothing for correct firing . the belt holds the brass case back against the bolt face . the belt sets the headspace on the initial firing . after the brass is fully formed , the brass can be resized to headspace off the shoulder . most new brass takes more than one firing to get fully expanded .
Peterson brass , now sells what they call long brass , for a few belted cases . the long brass is much closer to chamber dimension .

https://petersoncartridge.com/blog/peterson-cartridge-introduces-300-win-mag-long

the best way to work with new belted cases , is to form a false shoulder . this will help extend case life by making the shoulder blow forward , instead of stretching the case in front of the belt . here is a link on forming a false shoulder .

forming a false shoulder

all this false shoulder talk got my interest up , I had to do it . I wasn't sure if it would be worth the effort . I found there is nothing to this .if you have the means do it , it can only help case life . I doubt I have I have 15 minutes in getting things measured , until I had 5 pieces...

forum.nosler.com

Jim beat me to it. Neck them up to 7mm and then create a false shoulder and enjoy increased case life and no need to burn up bullets and powder just to form cases.

 

[JD338]

Jim beat me to it. Neck them up to 7mm and then create a false shoulder and enjoy increased case life and no need to burn up bullets and powder just to form cases.

^^^^This^^^^

JD338

 

[Jurome]

The Peterson brass was what got me checking this out in the first place. I knew the replies would be about head spacing on the belt, but could someone then explain how come the brass that mis fires is ONLY the brass that has that is virgin insanely short?
Help me out please…false shoulder, neck up to 7mm? I don’t understand what this means. How the heck would I neck up to 7mm? Then what do I do?

I don't have the tooling to do the false shoulder as the write up suggests.

If the manufacturers are going to make all new belted brass so darn short this is nothing new. They stretch, then life goes on. Shortened brass life? Sure, I guess. I have some on third and fourth firing doing just fine. A few months ago I was watching the marketing folks at Peterson (on YouTube) announcing the 300WM and 300RUM brass that is "normal length".

From what I have read for a long time on all the reloading forums...headspace off the belt only for the first fire, then after that its all shoulder?

If anyone could tell me if my gun is faulty because it can't shoot vigin Winchester brass? I knew the minute I posted this, there would be the "headspace is on the belt" replies, but it does not explain howcome the virgin brass is the only failure. It shoots all factory loads flawlessly. It shoots all my handloads that I have sized flawlessly, 100% of the time.

 

[jimbires]

I have no idea why the virgin brass doesn't fire consistently for you . is this brass factory primed ? if it is maybe bad primers . try to use your calipers and measure the belt width , and also the measure the case head to the top of the belt. this one will be tricky . maybe the belt isn't right . just a couple guesses of the top of my head .


I provided a link in my other reply to you . this link will go to another thread on this forum on how to form a false shoulder . there will be a few tools you'll need to get , to properly do this . a 7mm mandrel , and a mandrel holding die .


here is the link again ;

forming a false shoulder

all this false shoulder talk got my interest up , I had to do it . I wasn't sure if it would be worth the effort . I found there is nothing to this .if you have the means do it , it can only help case life . I doubt I have I have 15 minutes in getting things measured , until I had 5 pieces...

forum.nosler.com

 

[Jurome]

Hi thanks, no it was not primed brass. Previous owner had two bags of Winchester unprimed brass and made hand loads from them. I disassembled some of the loads for verification to ensure they were safe. His charges were accurate and spot on. His seating depths were consistent to 0.001", so I starting using some of them. Then the misfires started. I began my forensics; measuring my 2-4 fired previously fired cases, measured my factory ammunition shoulders, measured the misfire rounds then yikes...the only denominator was new brass and an incredibly short shoulder. Which I later find out is the norm for new belted cases. The loads the previous owner made from fired brass, and to which I verified were safe. ALL of them fired flawlessly.

Maybe the brass in these bags have a headspace issue at the belt too?

All is not lost, as I have already fire formed about 40 of these without any problems. They work just fine second time around.

 

[Jurome]

Maybe I have a weak spring? AI search on Google reports Model 70 post-production since 2020 has had some issues. Maybe the "new" belt headspace is just enough to be weak for the strike? For now I will disassemble the bolt and clean it. I would buy a new firing pin spring, but I am in Canada and all the inventory is gone (out of stock) that I can see. I would like to simply replace the spring with a Wolff and see if this solves the mystery.

Appreciate all the input thanks very much