.223 Issues - Need Advice Please

[Lovesbeer99]

I'm using a Rock Chucker Press with Lee 3 die set. Brass is RP with Winchester .224 FMJ BT, 55gr. The Brass was timmed and all within .002 of each other.

I loaded a batch of 50 and some of the bullets seated way deeper than the others. So I checked the remaining bullets and they did not measure consistantly. Ok so that accounts for why some of the bullets seated so far that I can't see the cannelure, but...

I have 4 different COAL's. I'm getting 1.710, 1.715, 1.720, 1.724. It's like a made several small batches or something. The overall difference is just too much, and I don't understand why a PRESS is creating the different COAL. I can understand the cannelure issue if the bullets are no consistant, but not the COAL. The press should creat the same COAL all the time. Any advice? Thanks in advance.

Lovesbeer99

 

[tbtrout]

Either you are not raising the ram all the way up each time or your dies are loose.

 

[Jim Watson]

Assuming your seating die and operating technique are right, it might very well be that you have bullets from four different lots or even off four different machines. Those FMJs are cheap for a reason. Their nose shape where the seating plug contacts is not the same from batch to batch.

 

[taliv]

the press doesn't seat using the point of the bullet. it's likely that if you measured from the ogive, they would all be the same length

 

[Walkalong]

Iv'e gotta go with Jim here. That is a big difference for slop in a press.

 

[Grumulkin]

the press doesn't seat using the point of the bullet. it's likely that if you measured from the ogive, they would all be the same length

This is true even with quality Sierra, Nosler and Berger match bullets.

Another thing I've had happen, is for the bullet seating die to pull the bullet out slightly whan the cartridge is removed. It happens if the neck is a bit loose. I've only had this happen with Barnes TSX bullets using a Lee seating die but I suppose it could happen with other combinations of dies/bullets.

 

[Khornet]

I'm pretty sure

that while presses don't seat at the point of the bullet, the punch doesn't reach as low as the ogive either. Usually it's somewhere in between.

Get a bullet comparator, such as Sinclair's, which is good and doesn't cost much. Then you can measure from the ogive, which is the really meaningful measurement. If they still vary widely, see the other comments.

 

[loadedround]

Have you checked the overall length of your cases? If not you may have cases of different lengths hence different overall seating lengths. All bottleneck rifle cases have to be trimmed after several loadings. Always check the simple things first.

 

[Idano]

loadedround,

Unless I am overlooking something I don't think the case length will affect the COL. Correct me if I am wrong but different length cases will only vary how much of the bullet is exposed. When you run the case and bullet into the die the base of the case rests against the shell plate and the bullet comes in contact with bullet seating plug so the overall case length is determined by the travel of the ram and not the case length.

 

[dcloco]

The real problem? There is two.

If you are using BULK full metal jacket or cheap bullets, the difference is in the bullet.

The other item, if you are using bullets with a plastic tip, the seating die is not made to use this type of bullet - squishing the plastic tip a little bit each time.

 

[matt33]

Are you sure your measuring correctly? I only ask because my loaded .223 rounds measure 2.22" - 2.26", depending on my bullet selection. I trim to 1.75". While I'm relatively new to reloading, I've found that most bullets have enough variation to give slightly different OAL's. For example, using RCBS dies and equipment, my 69 grain Sierra MK's range from 2.257" to 2.260". I've found ballistic tip style rounds to be the most consistent in regards to over all length. My spec's are in line w/ Sierra and Speer's published data.

 

[Lovesbeer99]

Update - Thanks for all the responses. I did measure correctly, I just didn't type correctly. My rounds are 2.210, 2.215, 2.220, 2.224 and I measured them again to make sure.

Since I didn't crimp them yet, I pulled some enough so that they were still seated, but needed to be run into the seating die again. I first tighted the die and I'm now getting better results. The range is now in the 2.220 and 2.224 area. I'm still having issues with a few specific rounds like 1 that is 2.255 and when I run it into the die, I doesn't even touch. I believe this is the round that proves the ogive and batch theory that Jim and Taliv stated below. I plan to load another 50 tonight and I will pay very close attention to what the results are. I'm also expecting that once I crimp these, using the Lee FCD, I might get a new measurement, but that is another post.

 

[Idano]

Lovesbeer99,

I suspected that the issue was with the ogive just like Jim and Taliv said. I have the same issue with bulk FMJ and it shows on paper, so for my money I have had better luck with Winchester SP, still some variance but not as drastic. By the way I wouldn't recommend crimping the bullets, .223 doesn't need it even for an AR. There is enough neck tension and the bullet is so light it won't move so all you will end up doing is putting more stress on the neck of your brass shortening its life.