bullet seating

[Jody Ward]

Just curious if I am the only one this happens to? Been reloading for a while and feel I'm very meticulous in measuring everything twice sometimes three or four. I prep brass and when I go to seating I can set die to measure 2.111 CBTO and seat two and then the third will measure 2.119. I zero calibers and try again with the same thing happening. I'm using Redding Competition seating die on this one but have also experienced this with Forster seating die. Do any of you run into this?

308 Winchester
Lapua Brass
loading Sierra 165 TGK's
Load is not compressed

 

[Walt Krafft]

What is your neck tension? How many times have the cases been fired? Do you anneal?

 

[wkdickinson]

I think you are likely seeing the variation in the length of the bullet between the ogive and the bullet tip (bullet OAL - BTO = OTT). I just measured 30 Sierra 116 TMKs and found a .007" variation in OTT.

 

[Jody Ward]

Using bushing die, brass has been fired 5 times, yes I anneal. I do not measure bullets, prolly need to start!!!

 

[ShtrRdy]

Measure a handful of bullets only to see how much the length of the bullet is different.

 

[Jody Ward]

Will check bullets.
thanks

 

[222Jim]

Retired engineer with all the baggage that carries, so I measure and record every cartridge I load.....

I got seating range down to +/- 0.001, i.e. Maximum - Minimum CBTO <= 0.002, by doing everything described above PLUS these three four other things:
(1) When setting up the press/die for CBTO, I make sure the first 4 or 5 bullets I use are typical of the box,
(2) I make sure the seating die gently yet firmly touches the shell holder with just enough force to take up any slack in the press' linkages, and
(3) I don't use compressed loads.

I've tried lubricating the inside of the case neck and/or bullet bearing surface and that'll help, but it's a pain in the butt and I'm not yet convinced lubricating improvement my results (including precision and velocity SD).

Here are CBTO measurements from 50 .308 cases I recently loaded (Sierra 168 MatchKing, Lapua brass that's been annealed):

 

[JMayo]

Getting the 3rd # can be frustrating. I go with the more than half goes to the higher # . Less than half goes with the lower #
Put it back in seater give it a couple of wacks !
Use the same motion start to finish with all.
Ie; show push or sharp wack

Shooting br,
the cases are full unless powder is tapped in slow rate.
Sometime My cases are so full that seating becomes a problem.

The base of the case can be thicker, a protruding primer.

 

[6BRAckley]

make sure seating stem is engaging the bullet on the bullet ogive, instead of the tip. If it is hitting the stem as it should then the problem is likely variance in the bullet themselves, which can happen with mass produced bullets.

 

[RabbitSlayer]

This is normal. Measure some factory ammo. It varies too. There is variation in the bullet and also on the first loading of new brass I notice it can be really bad. Graphite helps. Infact I barely worry about it on the first loading. I just use graphite and error towards the short side. I find seating then turning quarter to half rotation and seating again also helps.

 

[Bill Norris]

Several things come into play with getting consistent seat depth.

ck. seating die tight in press
ck. bullet tip bottoming out in stem (drill it out)
ck. bullet touching powder column (full case - use cordless toothbrush to settle powder)
ck. speed and bottoming out pressure with press handle stroke (apply equal pressure each round)
ck. bounce at bottom of press handle stroke (follow thru with hand equal pressure each round)
ck. consistent neck tension and neck thickness
ck. lube inside necks consistently
ck. bullet length base to ogive

 

[6BRA]

The only way you can lock a seater, is to sort bullets by BTO and then sub sort by OAL in that order. I wouldn't attempt this with bullets that are factory produced. Maybe Bergers. As stated the nose region of each bullet out of the same box same lot varys. When .003 can you knock you out of a seating depth node there is no other way. Its not you, its not your seater stem. Its your bullets!

 

[kyotekiller25]

Gives me fits also. That is why I just started seating long, then adjusting down to where I need to be. Back off the seater for the next bullet and repeat. This is the only way I can get consistent depths with ELDMs, otherwise they'll vary .010" or so.

It takes a lot longer to do it this way, but when you have OCD and anal as I am, it's the only way I've found that works for me.

 

[Leo_B]

Retired engineer with all the baggage that carries, so I measure and record every cartridge I load.....

I got seating range down to +/- 0.001, i.e. Maximum - Minimum CBTO <= 0.002, by doing everything described above PLUS these four other things:
(1) When setting up the press/die for CBTO, I make sure the first 4 or 5 bullets I use are typical of the box,
(2) I make sure the seating die gently yet firmly touches the shell holder with just enough force to take up any slack in the press' linkages, and
(3) I don't use compressed loads.

I've tried lubricating the inside of the case neck and/or bullet bearing surface and that'll help, but it's a pain in the butt and I'm not yet convinced lubricating improvement my results (including precision and velocity SD).

Here are CBTO measurements from 50 .308 cases I recently loaded (Sierra 168 MatchKing, Lapua brass that's been annealed):

View attachment 1761268

And the fourth remains top secret.

 

[jackieschmidt]

The trick for consistency with the Redding Competition Seater is do not rely on the break over of the linkage as a stop. Set it up so the shell holder comes in firm contact with the bottom of the die, giving a positive stop.

I use Redding dies exclusively in my 6PPC and 30BR.

 

[wkdickinson]

make sure seating stem is engaging the bullet on the bullet ogive, instead of the tip. If it is hitting the stem as it should then the problem is likely variance in the bullet themselves, which can happen with mass produced bullets.

That is the problem. All of the dies I have (Whidden, Forester, Redding) the seating stem diameter is significantly smaller than the comparitor (ogive). A few years ago when I was "chasing my tail" on this issue, I made a comparitor insert as close to the seating stem dia. as I could - amazing, when using that insert to measure loaded length, all of my round were within .0005". It is the inconsistency of the bullet form that is the problem. In my measuring, Sierra is the most consistent and Berger is the worst (between the two). Yet Berger bullets shoot amazingly well - why?

 

[222Jim]

The trick for consistency with the Redding Competition Seater is do not rely on the break over of the linkage as a stop. Set it up so the shell holder comes in firm contact with the bottom of the die, giving a positive stop.

I use Redding dies exclusively in my 6PPC and 30BR.

I use Redding Competition dies too.

 

[222Jim]

And the fourth remains top secret.

Three. Okay three. Just checking to see if you read this?

 

[jpjulian]

IMO Redding seating stems suck. They crack. Then they don't slide smoothly. They don't like heavy bullets. They don't like VLD's. That's my opinion and I'm sticking to it. And Redding has told me in writing they think I abuse their precious seating die. Minor rant off............

 

[mgunderson]

Any chance these are liquid cleaned cases? I see this level of inconsistency with new un lubed cases. Almost all dry tumbled cases have been more consistent for me.