Measuring seating force

[memilanuk]

Hello all,

The Brown Santa truck dropped off a package from PrecisionReloading.com containing a new K&M arbor press with the seating force measurement package. I set it up and started tinkering (of course!) using some 6mm BR stuff I had sitting on the bench.

I'm kind of curious what other people's experiences have been with setups like this - any observations worth noting, etc.?

TIA,

Monte

 

[camac]

Monte, I do not have one but have been interested in it so would love to hear about it. I set up a Lee challenger press with short handle some time ago to do my seating (use rockchucker for other processes) so that I could "feel" seating force more easily. It has helped on several occasions to iron out a problem.

 

[UK]

mine arrived last week from Grafs, $70 to fedex to the UK but its only money eh!
I have ordered a digital indicator that reads max deflection and holds that reading for every round you seat, a standard indicator flips to quickly to read the max force accurately but once I played with it you can get a comparative reading when the seating operation finishes, I measured new brass against 4x fired and the reading was quite different on the two types, I must say though I much prefer the K&M press itself to the Sinclair arbor press.

 

[johara1]

I've used one for a year now and it works ends ,the i think it feels the same to a number. Each .001 i think is a lb. so i found how far i can go and keep the vertical tight. It really helps at long range.....jim

 

[memilanuk]

The little bit I've played with this thing so far has answered (probably) at least one question... got some neck tension issues sorted out (hopefully) in the wife's new 6mm BR.

One problem I seem to have so far (granted, I've only seated about 6-8 rds with it at this point) is feeling where the bullet stops seating and where I'm staring to just compress the washer stack once the seater is all the way down.

 

[DougMH]

I'm currently working on a way to test required bullet seating force... before bullet seating. I can't go into detail, but if it works out in testing I'll pass along all information. I will also say it's considerably cheaper than a K & M Arbor Press w/ Force Measurement and a Wilson seating die.

You might say, why would you want to test for seating force before actual bullet seating. Efficiency mainly. Here's my reasoning:

Say you have 300 cases that you’ve prepared. You need 100 cases for an upcoming match. You start seating bullets using a system like K & M offers for measuring seating force. What if you don’t come up with 100 the same out of the 300? You’re going to have 1) prepare more cases and 2) have a bunch of odd lot rounds lying around.

With my method, provided it proves itself in testing, if you have 100 cases that all force weight the same, then you've got 100 cases for your match… and no leftovers. Also, on future preparations, you can stop when any category reaches the number of rounds you need for a match. Say I had 300 cases and I’ve got the following spread (note, my method will likely require less force than actual bullet seating, but it should be proportional):

60 @ 6lbs
80 @ 7lbs
92 @ 8lbs
68 @ 9lbs

I would only have to keep preparing cases until any of those weight categories reaches the 100 mark. Then I could make 100 rounds with NO leftovers. Say I hit 100 of the 8 lbs sort group first and had the following distribution:

66 @ 6lbs
90 @ 7lbs
100 @ 8lbs
78 @ 9lbs

I make complete rounds out of all the 8 lb sort group and am left with

66 @ 6lbs
90 @ 7lbs
0 @ 8lbs
78 @ 9lbs

Another match comes up and I start prepping cases until the next category hits 100. Maybe something like…

88 @ 6lbs
100 @ 7lbs
35 @ 8lbs
90 @ 9lbs

I use the 100 @ 7lbs for the next match.

Never do I have whole rounds sitting around waiting for mates. Will I have to change my sight settings when using 6 lbs instead of 8 lbs? You may, a click or two possibly. But you won’t be using stray odd lot rounds for those spotter/foulers. With my method, you can use the same quality rounds you’ll be shooting in the competition.

And what if you come up with another crucial step in your reloading process? You might be able to rework the prepared empty cases. If you have entire rounds laying around, your only choice is to shoot them all as spotters or foulers or pull their bullets (risking scaring them in the process), dump the powder and hope you don’t have to waste perfectly good primers also?

Stay tuned

 

[Donkey]

Very nice Doug.

Do you have a time line worked out for testing your method?

Thanks for the very interesting contribution
Jason

 

[DougMH]

Very nice Doug.

Do you have a time line worked out for testing your method?

Thanks for the very interesting contribution
Jason

All the parts should be here today or tomorrow. The parts I'm waiting on are not really associated with reloading in any way. It's just my adaptation. The results may turn out to be totally unacceptable, but I don't think so. Even if this particular method doesn't end up working, I'm still devoted to the concept of determine seating force prior to actual seating.

I know it's possible, but I'm not sure one of the parts I have on order for it is going to be up to the task and/or accurate enough in its force measurement capabilities.

Doug