Home
Posted By: CaneSlinger Factory crimp? - 01/12/12
I had a bunch of .270 Win. handloads that I didn't have any idea what the loads were. So I pulled the bullets, recharged them and seated 140 grain Sierra Game Kings.
Some of the bullets seated quite snugly, but others took very little effort to seat.
I bought a Lee factory crimp die and I was thinking of setting it up to just put a bit of a grip on the bullets. The Game Kings don't have a cannelure so I wasn't planning to try and make it bite into the bullet, just snug them up enough to make sure they don't move in the magazine during recoil.
What do you say? Is this a good idea?
Posted By: Youper Re: Factory crimp? - 01/12/12
Crimp half of them, shoot them all, and tell us what you find out.
Posted By: Magnum_Man Re: Factory crimp? - 01/12/12
Should be snug enuf just seated without any crimp,last I knew nobody makes a tube feed 270. Like Youper says time for you to bench test them for accuracy so you can see what you been doing to your loads, improving or degrading them accuracy wise. good luck. Magnum Man
Magnum Man
Bullets can move in the case from recoil in a box magazine if they are not snug in the neck
Posted By: Magnum_Man Re: Factory crimp? - 01/12/12
Originally Posted by BobnRoy257_b4_Bob257AI
Magnum Man
Bullets can move in the case from recoil in a box magazine if they are not snug in the neck


Yes, that could happen,but when is the last time you have seen it? Did you think to question whether your dies were right or that you might do more than a partial neck size? My 338 Win Mag and 35 Whelen both have noticeable recoil yet I haven't seen them move yet. What specific cartridge are you talking about ? I've never had any 270's move from inertia or battering in my M700's.Magnum Man
Posted By: nifty-two-fifty Re: Factory crimp? - 01/12/12
CaneSlinger,

That is an excellent use for the Lee Factory Crimp Die

Without a cannelure the die will give you a nice, consistent taper crimp. You determine how much crimp you want by turning the die in and out slightly to get the right feel.

If you look at how the die is made, truly elegant in its simplicity, you will see that it can only crimp so much. Lee claims that it won't crimp enough to damage most un-cannelured bullets. I know I never have, but I haven't tried to. I put a mild to moderate crimp with the Lee dies on almost all of my centerfire loads.

I am usually not worried about bullets moving in the magazine, but I do believe that Lee crimping gives me more consistent neck tension. I see no downside to Lee crimping at all, except the little bit of work for the extra step.
Posted By: nifty-two-fifty Re: Factory crimp? - 01/12/12
Just pulling bullets and re-seating different bullets without resizing the neck would certainly reduce neck tension and it seems reasonable that some would be loose enough to move in the magazine.

The Lee Crimp Die will fix that.
Posted By: CaneSlinger Re: Factory crimp? - 01/12/12
Thanks.
I'll give it a whirl. I've never had a problem with bullets moving in the box magazine of my BAR, but some of them did seat with very little pressure.
I thought, if nothing else, it would make the neck tension more consistent.
Posted By: Tennessee Re: Factory crimp? - 01/14/12
The crimp die may keep the bullets from moving but I expect you will see unusually high SD and ES due to varying neck tension and the resulting varying friction over the entire gripping length of the neck.

That being said sometimes a rifle and cartridge does exactly what it wants to do no matter what I expect.

Posted By: Crow hunter Re: Factory crimp? - 01/15/12
Originally Posted by Magnum_Man
Originally Posted by BobnRoy257_b4_Bob257AI
Magnum Man
Bullets can move in the case from recoil in a box magazine if they are not snug in the neck


Yes, that could happen,but when is the last time you have seen it? Did you think to question whether your dies were right or that you might do more than a partial neck size? My 338 Win Mag and 35 Whelen both have noticeable recoil yet I haven't seen them move yet. What specific cartridge are you talking about ? I've never had any 270's move from inertia or battering in my M700's.Magnum Man


I've seen them move in cartridges as small as the .257 Roberts. I have a bad habit of single feeding a new cartridge on top of a magazine that's full. By doing that I can have a round in the magazine through 10-15 shots. Trust me, an uncrimped bullet will move on you if you leave it there through 10-15 shots. Try it and see, you might not be able to detect it with your eyes but stick the calipers on them an it'll become obvious. I have lee factory crimp dies for all my bolt rifles now.
Posted By: jwall Re: Factory crimp? - 01/15/12
Originally Posted by nifty-two-fifty
Just pulling bullets and re-seating different bullets without resizing the neck would certainly reduce neck tension and it seems reasonable that some would be loose enough to move in the magazine


Sound Advice right there.

[quote=CaneSlinger]
Some of the bullets seated quite snugly, but others took very little effort to seat. (quote]

You do have inconsistent neck tension. If the Lee die doesn't fix it AND/OR your accuracy is off, it may take resizing to get the consistent tension needed.

Good Luck
Posted By: KiloCharlie Re: Factory crimp? - 01/15/12
I didn't start handloading until about 1993, by which time the Lee Factory Crimp Die was available. Since then, I have crimped every cartridge I loaded, no exceptions. I generally use cannelured bullets (Hornadys and CoreLokts, mostly) but have found that crimping uncannelured bullets does not create a problem. Given that only a quarter of my ammo is for tube-fed levers, the crimp is not generally necessary.....but it's also not detrimental.
© 24hourcampfire