Lube groove on lead bullets. Crimp?

Pond James Pond

New member
On some SWC I have just bought, there is a groove filled with some sort of blue wax. (not loaded much lead before)

Should I be crimping in this groove or should it be left alone and the crimp be made straight into the wall of the bullet?
 
When lead bullets are pushed through a lube die, the lube is applied non-selectively to the entire bearing surface of the slug. It won't hurt to crimp in the crimp groove regardless of it being filled with lube.
 
Most cast bullets have both a lube groove and a crimping groove, with the crimping groove being further up the bullet and having a sloped side instead just being a square notch. A picture of your bullet would help us help you.

If your bullet has only one groove, do not crimp there - you will displace some of the lube and the OAL will most likely be too long (also load pressure too low due to more case capacity). SWC without a crimp groove can be lightly crimped over the top shoulder, but that is not ideal. Better to load with good neck tension and just barely crimp the mouth below the shoulder. This will always be fine as long as you are loading to special levels and not magnum.
 
There is only one groove on this bullet. It is about 2mm wide and filled with the blue lube I mentioned. There is plenty of bullet above the groove.
 
When lead bullets are pushed through a lube die, the lube is applied non-selectively to the entire bearing surface of the slug. It won't hurt to crimp in the crimp groove regardless of it being filled with lube.
Au contraire. Most cast lead bullet designs have one or more lube grooves at the base of the bullet and a shallower crimping groove near the nose of the bullet. Both Lyman and RCBS Lube-Sizer machines, as well as Star, can be adjusted to only fill the lube grooves and leave the crimping groove empty of lubricant.
 
What caliber are you loading for? There are cast bullets designed for semi-autos that only have the lube grove... Obviously because semi rounds require a taper crimp...
 
How about you post a photo of these bullets because as usual some of these posters are telling you half right information? If you are loading .44 Special loads a good crimp is very important to getting a good powder burn and not having a bullet move in the case due to recoil.
 
If there is no crimp groove, crimp over the shoulder. The lube groove is near the rear of the bullit. Flat base or Bevel base? A picture would be nice or ID where the lead bullet came from.
 
Mr. P,
Unless you are loading the Specials to magnum velocities;

I would recommend picking up (or ordering from *bay)
a taper crimp die made by Lyman or a Redding taper crimp profile die.
I am very pleased with both varieties.

There may not be much bullet movement with light .44 Spec.
loads,
but I feel that putting a consistent light to moderate taper crimp
will help control velocity variations (as mentioned by hartcreek)
and result in a more accurate load.

Roll crimping into the filled lube groove can get your seating die a little messy
after a while and enough of the hard lube wax build up in your
seating die will result in a gradual deepening of your seating depth.

My .02, JT
 
Taper crimp , made straight into the wall of the bullet. No roll crimp. This would apply to your photo posted below. The OAL should leave a little of the bullet lip exposed. Like here in my photo.
 
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I am having difficulties getting my camera to marry up to my computer so actual photos are a bit tricky, but I found these online via google which bear a very close similarity (read almost identical) to what I have bought so you can see the proportions:


10mm-40SWComparo_zps8d3cf976.jpg


The only real difference is that mine have a tiny bit more of a ledge between the truncated cone portion of the bullet that rises away and the bullet's main body.
 
Bullets with no obvious crimp groove and usually one lube groove are "normally" used in/designed for semi-autos and should be very lightly taper crimped. Seating depth of these bullets should start with recommended OAL from a reloading manual...
 
You do not need to crimp unless you're loading hot loads or shooting a lever action. Target loads are not crimped at all. If you do need to crimp, use as little as possible to hold the bullet in place and no more.
You do not load the Specials to magnum velocities either.
The Lee Factory Crimp, is a taper crimp for pistol cartridges and roll crimp for revolvers. As in 9mm is taper. .44 Special is roll.
 
Crimping those depend on how hard they are. I have crimped the with a roll crimp right into the bullet a couple thousands but otherwise trhose need to be crimped just past the shoulder.

With regards to target loads....for some people 7 grains of Unique with a 240 grain bullet in a .44 Special case IS a target load but it still had better be crimped.
 
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