Bullet seating problem

[GreyAwakened]

Here's a mystery for you to solve:

- I crimp and seat bullet to .44 Magnum with Lee carbide die
- I set a light crimp (1/4 turn) and seating depth to 1.610" (OAL)
- Most (95%) seats ok to the desired OAL, but the rest, seat too deep, to about 1.570"

I understand that there is a normal small variation from the bullet and case etc, and these are quite small, and make the OAL vary +/-0.005"

Why on earth some of the bullets are seated so deep?

The bullet I am using is copper plated 215 grain flat point, flat base type, no crimp groove, bullet diameter 0.432". They seem to be fairly soft. If I set the crimp any heavier, a visible indentation in the bullet will form - like a crimp groove.

Before the seating phase, the bullet plating is shiny and intact. Afterwards, it has scratch marks a bit above the case mouth, and the scratch marks go round the whole bullet. The scratch band is about 1/20 inch wide and the bottom of it seems to be a clear line.

Inside the seating die, before the seating stem, there is a ridge which has a small amount of copper shavings. I think the ridge is the crimping shoulder which wedges the case mouth into the bullets crimp groove (if there is such in the bullet).

It seems that the bullet hits the crimp shoulder, but that shouldn't happen? Right?

What's going on? What am I doing wrong?

Edit:

Lee instructions state for bullet diameter the following:

.429 - .431

Could the problem happen because of the +.001 bullet diameter?

 

[CZ57]

GA: I don't use LEE dies, someone else can better help you there. Coupled with the top-dead-center feature that REDDING presses have, their dies will keep your OACL tolerance to +/- .001". The harder titanium carbide ring in the resizing die is the reason for the price difference. Bullet length variations are the norm, so whenever possible, you want to be seating on the bullet's ogive with jacketed or round nose bullets.

As far as crimp goes, you don't really need much of it with bullets that are .432". With light loads, you could skip crimping altogether. If you use a powder that requires more bullet "pull", taper crimping will be better for softer bullets that don't have a crimp groove. The deformity you are seeing is because the roll crimp you're using is making it's own crimp groove in the bullet. The shavings may be coming from the case digging into the bullet.

You don't really know if the bullet is overdiameter by .001" unless you know the groove diameter of the barrel. Could be more, or less. Slugging the bore will determine that.

 

[taliv]

put some butter on it!


(just kidding)

 

[Steve C]

I think what you are seeing, esp. the scratches, is caused by the seating stem. Most dies are shipped with a round nose seating stem some are set up for SWC. For the most part this works for most bullets but you can get some nose deformation with exposed lead JHP's or a little rounding on the bullets nose on SWC's. The bullets that are seating deeper could be ones with a slight wider nose that don't fit as far into the seating stems round nose base OR the bullet is entering the seating stem at a slight angle and is contacting it differently. The later situation is likely caused when the bullet is started at an angle when its fed on top of the case or its pushed a bit into the case before entering the die as the bullet will usually self center if loose enough. One solution would be to see if Lee has or will make a flat nose seating stem for you. RCBS used to offer different seating stems for their dies with a flat nose for wad cutters, a SWC style and a RN style.

 

[Ol` Joe]

I think Steve has the answer to your problem. RCBS and Dillon both offer different seaters. I`ve had this very problem in the past and a new seating stem cured it.

 

[CZ57]

Is this bullet a RNFP, or a truncated cone? Regardless of the flat point, if it has a rounded ogive, I would use a round nose seating stem. If it's a SWC or Truncated Cone with a flat nose, I'd go with a SWC, or flat seating stem. The out of alignment issue is more likely to be caused by a SWC seating stem. A round nose seating stem and seating by the ogive will better correct alignment of a bullet with a rounded ogive (nose profile).

Editing to add that seating and crimping in two seperate operations will probably eliminate the OACL anomalies.

 

[Bronson7]

I respectfully disagree with CZ57's assessment. If the bullet has a flat nose, regardless of wheather or not it has an ogilve, A flat stem should be used for seating to minimize oal variation. The variations in olgive will cause variations in oal. Variations in bullet length will not affect oal, but will affect bullet insertion depth. That would be like saying variations in you brass length will cause variations in oal (again, it will cause variations in bullet insertion depth). Picture in your mind telescopic pipes.
Bronson7

 

[GreyAwakened]

my guess

Hi guys,

I have come to the conclusion after investigating the matter more, that the problem was caused by overdiameter bullets. The bullet does not need to touch the seating stem to get scratched. There could have been also manufacturing variance in the bullet diameter, causing some bullets to seat ok, and some bullets to hit the crimp shoulder so much as to seat it too deep.

The Lee die for .44 Magnum/Special can not be used well with .432" bullets. Their tolerances, as per instructions, allow for .429-.431" bullets.

Thanks for the ideas, though

 

[CZ57]

Bronson: that is a solid point, but it assumes that there is better uniformity of the flatness of the nose (from bullet to bullet) than the curvature of the ogive. It also assumes that the bullet will be seated in correct alignment, even when the stem is contacting a small portion of the bullet nose. That has not been my experience with cast lead bullets with a rounded ogive, maybe it's so with plated. Measure bullet length at various points around the nose and you'll see what I mean. Any lead bullet that comes out of a mold has less surface area contact with the mold at any point of its curvature than it does on the nose and is less likely to have variations of the ogive. I get very uniform OACLs with RNFP bullets and I seat with the roundnose seating stem.

 

[Bronson7]

Point taken CZ. The flat end of the bullet needs to flat to minimize eccentricity. I load SWCs and RNFPs using a flat stem with no problems in that respect. The RNFPs have a large flat area which is well suited to a flat stem while the SWCs, DO, as you point out, have a very slight curvature at the tip, which may give some folks trouble with eccentric seating using certain seating dies and a flat stem. I'm using a Hornady New Dimension die which does a very good job of maintaining concentricity with oals in the .001-.002" range. Thanks for your response.
Bronson7

 

[snuffy]

"The bullet I am using is copper plated 215 grain flat point, flat base type, no crimp groove, bullet diameter 0.432". They seem to be fairly soft. If I set the crimp any heavier, a visible indentation in the bullet will form - like a crimp groove."

GA, who makes this plated bullet? If it's Ranier, then they are NOT resized after plating, refered to as double struck. Plated bullets are cold swaged from nearly pure lead, then plated. Ranier does NOT then size them, they depend on the plating to be of uniform thickness to bring them up to nominal diameter. If they're Berrys plated, they double strike SOME of their bullets. The only plated bullet company that double strikes ALL their bullets is the old west coast bullet company, now called extreme bullets, http://www.xtremebullets.com/index.htm

That said the crimping shoulder in the die is only going to allow a bullet of .431 to pass through without getting scraped, If some of those plated bullets are bigger than that they will be scraped and could be seated deeper by the crimping shoulder.

 

[GreyAwakened]

yes

snuff,

thanks for your reply. The bullets I use are made by a Finnish bullet company called Archipelago Bullets. They re-strike *some* of their bullets, but not the .44's. They state clearly in their package the diameter, and the bullets are fairly consistently in that size. I just didn't know that the reloading dies have so tight tolerances.

I'm not sure if it will help, but I'm going to try freezing the bullets before reloading them, next time. Hopefully they shrink a bit in size, and do not cause so many overseated cartridges. I still have hundreds left.