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Rilfle Crimp Dies
bambambam
Member Posts: 4,818 ✭✭✭
I'm going to have some time to kill and was wanting to crimp some of my loads that are made up.
I bought a Lee Factory Crimp Die (90821) for my 7mm Rem Mag. I had a question about this die. I notice a ring and when screwed down enough you get a castle look to the top of the neck. The directions don't say anything about the marks and how much to crimp without hurting the brass. It does say that when you lower the ram and the cutout's on the collet touch you have reached max crimp.
How deep should I crimp?
Also are there other crimp dies that I can buy? I was looking for a crimp that didn't damage the neck so much.
I bought a Lee Factory Crimp Die (90821) for my 7mm Rem Mag. I had a question about this die. I notice a ring and when screwed down enough you get a castle look to the top of the neck. The directions don't say anything about the marks and how much to crimp without hurting the brass. It does say that when you lower the ram and the cutout's on the collet touch you have reached max crimp.
How deep should I crimp?
Also are there other crimp dies that I can buy? I was looking for a crimp that didn't damage the neck so much.
Comments
Open collet put in a round then turn collet until you feel it touch your case, then
? or ? turn to adjust crimp. The collet will be down inside the die not like pic.
When the collet is closed that is max and is more crimp than is needed.
All the brass cases must be trimmed to same length,
and after crimping and especially before going hunting or too the range, carefully and gently make sure the shells chamber easily, be careful when testing for chambering, because if crimped too much or some of the brass is longer you will get a bulge in the brass and a stuck case.
I tested a 223 lee factory crimp die about year ago testing accuracy of crimp vs non crimp. In my 223 my best accuracy was without a crimp at the high velocity loads, but at very low velocity reduced loads (1600fps) for squirrels, varmits, pests, I got best and very good accuracy by using a bullet with a crimping cannlure and using a standard bullet seating die adjusting for crimp in the cannulure.
Don't know why he wanted to crimp a 7mm mag?
If it's just to hold the bullet into the case tighter, why not just use a bullet with a crimp cannulure and a standard bullet seating die set for crimp. Maybe when it recoils, it's shaking the bullets loose from the spare shells in his pocket?
some of the you tube stuff you need to take with a grain of salt, though!
I just guessed it would help me achieve a better burn and get a higher velocity. I don't get the speed that all the different books publish and just thought I'd try this to see.
I'm going to have some time to kill and was wanting to crimp some of my loads that are made up.
I bought a Lee Factory Crimp Die (90821) for my 7mm Rem Mag. I had a question about this die. I notice a ring and when screwed down enough you get a castle look to the top of the neck. The directions don't say anything about the marks and how much to crimp without hurting the brass. It does say that when you lower the ram and the cutout's on the collet touch you have reached max crimp.
How deep should I crimp?
Also are there other crimp dies that I can buy? I was looking for a crimp that didn't damage the neck so much.
bambambam,
From my experience with Lee Factory Crimp dies, I believe what you are describing is normal. This die is supposed to crimp like factory rounds, and if you look at current production ammo the rounds have marks similar to what you describe. When using the Lee dies, I start with a little crimp and move heavier until I get a firm crimp, and it is rare that I use max crimp (collet completely closed).
I am just wondering why you want to crimp 7mm R. Mags? My 458 yea a little on hunting loads. Tube magazines for sure.
The 7mm Rem Mag produces more than enough recoil to unseat a bullet in the magazine if crimping or neck tension is not sufficient.
I too, find that the ammo makers and the reloading books do seem to be a bit optimistic with the data for the 7. I joke that the biggest difference between the 7 mag. and the .270 is that the 7 has 2 more inches of barrel and weighs a pound more! However, I do own five rifles chambered for the 7 Rem. Mag. They seem to do better with the heavier bullets (160 & 175) and the slower powders. A load that shoots well in all of my rifles is the 175 gr. Hornady spire with Reloader 25 powder and Federal 215 primer.
Thanks Ambrose,
It's alway good to hear what other people have good luck with. I'm still experimenting with load developement on this gun. I started a few months ago and the weather in IL and my time has not been allowing me shooting time.
I punch paper, coyote,& deer hunt with this gun so far. I'm playing with the 130gr-160gr ballpark. I have H1000, H4831SC,& H4350 powder. Speer 130, 140 Game King bullets and Hornady 139SST,154SST,& 162A-MAX bullets. WLR primers and Fed215 primers.
I have loaded 5 of each powder(if applicable for powder/bullet weight compatable, ex. some 162gr bullets aren't going to have a load in the H4350 powder) with each bullet, with each primer.
I don't really mind which of the combinations end up being the most accurate round as the 130,140,154,162 will all do what I want.
I have a long way to go before I find that magic round for my gun.[^]
Okie,
Thanks for the link. I watched it and about a hand full of the related videos. I have always welcomed as may points of view about a subject. I take in as much info from others as I can get and take whatever tips I find relevant and apply them. It has really been a blessing having so many reloaders on GB to learn from.
76K20,
I have always noticed that the factory ammo I used to buy didn't have the ring or castle mark(to much crimp). I think most of the ammo I bought had a cannalure with roll crimp. Good to know I'm not the only to notice something.
True, the Lee die doesn't depend on case length for the crimp, but,
Crimp or no, brass that is allowed to get too long can cause real problems. Once the brass starts getting crammed into the taper of the throat, pressures can skyrocket.
So, yes, you don't have to worry about all cases being the same length to obtain a uniform crimp with the Lee die, but you for sure need to keep OAL within specs to avoid the possibility of high pressures.[:D]
Not this deep.