.008 difference in seating depth

[captnmo]

I just started using the Redding competition seating die and having inconsistent depth. I'm measuring off the ogive and get anywhere between .003 to .008 differences. I can tell the amount of pressure I put on it when seating makes a difference as well, like there's a bit of slop in either the die or the press. Probably the press, it's a Lee. Any suggestions? Should I be concerned or just work on being more consistent with the stroke of the press? I'm seating Hornady match .308 168 graing bullets into once-fired Federal brass.

 

[427Cobra]

Re: .008 difference in seating depth

Sort the bullets first by Ojive then load'em up

 

[former naval person]

Re: .008 difference in seating depth

Probably brass prep will help. First...clean the brass. Tumble preferred. Resize full length, fitting to chamber. Clean and degrease again. Trim to length. Deburr and chamfer. Polish inside the necks with 0000 steel wool on a brass or nylon brush. Lube inside the necks with graphite in alcohol. (LockEase)) Use a Q-Tip. Clean primer pockets and prime the cases. Make sure the holes are clear of cleaning media. Charge the cases. Seat the bullets...start them in the necks by raising the ram just till they enter the case necks. Turn the cases 1/2 turn and seat the bullets all the way. Leave the handle down for a long count of 10...I measure the charge and then fill the next case. Then raise the handle and check your runout and seating depths. Bet you it will be much better. JMHO

 

[Fuzzball]

Re: .008 difference in seating depth

Ah, don't think it's possible for either a die or press to change the effort in seating pressure. Suggest you look at variations in the case mouths.

 

[DanSavage]

Re: .008 difference in seating depth

I'm having the exact same problem! I also have a lee press but loading 168 A Max's. I think it is the press because if I have a bullet come out a little long, I put it back in and press harder and the bullet will come out a little shorter than I wanted. Then the other night I laying in bed I came across a solution. A cam over press. This would allow for the exact same maximum height of the ram. I'm not exactly thrilled with the idea of getting another press but it just may be the answer to getting repeatable seating depths, it sure would save alot of time and screwing around.

Dan

 

[captnmo]

Re: .008 difference in seating depth

427, I'll try that, but they're all out of the same Hornady Match bullet box I bought off the shelf.

 

[DocB]

Re: .008 difference in seating depth

Good day,

2nd Cobra, you can also try cleaning the inside of the case neck with 4-0 steel wool on a brush.

HTH,
DocB

 

[Ratbert]

Re: .008 difference in seating depth

Your problem is probably differences in the ID of the neck. Tighter necks are requiring more force and so jamming the steel seater deeper into the soft copper jacket of the bullet, resulting in the bullet itself not seating quite as deep when the seater reaches the bottom of it's travel. I was doing some testing with pin gages a while back and it doesn't take much difference in neck tension at all to get very different sensations when seating bullets. Something like less than 0.0015" can make a very noticeable difference in the force required to seat, depending on what your target neck tension is and the caliber of the projectile.

Annealing, neck turning, etc can help get uniform neck IDs.

 

[captnmo]

Re: .008 difference in seating depth

Interesting. I never thought the neck tension could have affected the seating depth, but it makes sense. I am fairly new to this.

I FL sized all the brass with the Redding competition die set. I may try the Redding S-type neck die and experiment with different neck sizes.