Seating question

What brass? Consistency starts with the right components.

What is your es/ sd on the loads? That matters a lot more than how variable you perceive the seating force to be.

I would never put lube near my powder and it’s completely unnecessary for seating.

You absolutely do not need an amp press to shoot low single digit sd.

People will likely try to tell you that you need a mandrel or that seating force matters. Neither is true though.

The only Forrester collet dies I van find anything about are bullet pullers. Can you link some more info on the die?

Got a drill, sockets & torch? That does it for me. Consistent seating depths to .001 of CBTO.

Ronin22 said:

Got a drill, sockets & torch? That does it for me. Consistent seating depths to .001 of CBTO.

Click to expand...

This worked for me when I had your problem. When I first started loading for rifles to try to make accurate rounds I wasn’t using the best components, but I was getting exactly what you are describing. I decided to try annealing by hand and tried 50 cases or so, problem went away. So then I bought an actual annealer and incorporated that into my brass prep.

It sounds to me like there is something funky with the brass. I've used the Imperial dry neck lube in the past with good results.

Is the brass all the same manufacturer and lot? Fired the same number times?

How do you measure your seating force? If it's by "feel" ... then (respectfully) you don't honestly know. I solved that problem initially with an Arbor Press (with inline dies), and eventually solved it forever with my AMP Press. "Knowing" is the first step in "fixing". It sounds like you're financially constrained related to reloading tools. If that's the case, then it will be a tough problem to solve.

An old boss of mine early in my career told me something I've never forgotten:

"It's not a 'problem' if you can solve it with money. It's an 'expense', and resolving the issue is actually a budgeting and prioritization exercise."

Grizzgup said:

Hello all.

When I go to seat bullets I’m noticing a substantial difference in the amount of force required to seat them. I measured all the case necks and they’re all the same. I’m using forster collet dies with a rock chucker press. I know the best way is to use an electronic press with expanding mandrel dies, but that’s not going to happen anytime soon. I lube all my cases necks with imperial dry neck lube, and am wondering if varying amounts of that can make a difference in the amount of force required to seat the bullets, or if it isn’t a factor at all. I know one of the keys to accuracy is consistent neck tension, and I’m afraid that’s where my hang up is with extreme accuracy. I’m currently shooting just under 1 MOA, but know that several of my guns are capable of more than that.

Click to expand...

Personally, I think hits against using a dry graphite lube like the Imperial to be bunk. Its fine in my experience.
As for seating force....aside from the annealing that's mentioned above by some, exactly how do you know what the interference fit (neck tension)?

Just measuring the outside of the neck?

Frankly, and again in my opinion, measuring the outside of the neck is a second order measurement and depending on neck thickness consistency may be totally misleading.

Get some pin gauges and directly measure what you really want to know....i.e. the inside diameter of the neck.

You don't need to spend a fortune on pin gauges....I bought Vermont Tool gauges from Travers....they are like $4-5 each


Now, if you find that your inside diameters (I'm assuming you use the expander ball of a full length sizing die) are not consistent, get a mandrel die body and mandrel from 21 Century.....good product and not too damn expensive (well, all of this precision rifle stuff is pricey but hey...that's what obsessions are all about lol).


Finally, do you trim your cases? In particular, do you trim to get an inside chamfer? This too will make a difference.

And finally, as mentioned above also, do you chrono your loads....and in particular have you determined your SD? Who cares about how seating feels if the end result (the SD) is very good and consistent.

Best of luck.

rustyinbend said:

How do you measure your seating force? If it's by "feel" ... then (respectfully) you don't honestly know. I solved that problem initially with an Arbor Press (with inline dies), and eventually solved it forever with my AMP Press. "Knowing" is the first step in "fixing". It sounds like you're financially constrained related to reloading tools. If that's the case, then it will be a tough problem to solve.

An old boss of mine early in my career told me something I've never forgotten:

"It's not a 'problem' if you can solve it with money. It's an 'expense', and resolving the issue is actually a budgeting and prioritization exercise."

Click to expand...

Yes, you are correct, you don’t actually know unless you measure. But in my case, some would seat so easy you almost think something was wrong, like almost no resistance. Or, some could be kind of hard, and everything in between. Now everyone feels exact the same (wether they are or not I don’t know, like you said, they need measured,)

If your cases are seating that inconsistently, and you're sizing correctly and using a Mandrel as your last step, then there's something wrong up-stream. Do you anneal? If yes ... how?

rustyinbend said:

If your cases are seating that inconsistently, and you're sizing correctly and using a Mandrel as your last step, then there's something wrong up-stream. Do you anneal? If yes ... how?

Click to expand...

03machstock said:

This worked for me when I had your problem. When I first started loading for rifles to try to make accurate rounds I wasn’t using the best components, but I was getting exactly what you are describing. I decided to try annealing by hand and tried 50 cases or so, problem went away. So then I bought an actual annealer and incorporated that into my brass prep.

Click to expand...

I had replied to the op earlier on just telling him about when I had the issue. No mandrel, I was using bushing f/l sizing dies, and wasn’t annealing yet. Cheap pmc brass. Started annealing, went away.

03machstock said:

I had replied to the op earlier on just telling him about when I had the issue. No mandrel, I was using bushing f/l sizing dies, and wasn’t annealing yet. Cheap pmc brass. Started annealing, went away.

Click to expand...

The combo of (a) annealing, (b) bushing die, (c) mandrel, and (d) AMP Press, for me, is unbeatable and gives me very repeatable results.
Oh ... and throw in a little NeoLube #2 before the mandrel step.

What bullet, what caliber, what brass, what kind of lube when sizing?

If the case mouth isnt chamfered/deburred the inside edge of fired brass will have a burr on it. Even new brass has some edge, attached is Alpha 6BRA brass.

Using flat base bullets will give varying seating pressure that you can feel in the press handle.

Others have mentioned annealing, when you can feel the brass requiring more effort to draw the expander ball out of the neck, then its probably already time to be annealing.

I dont love neck sizing only, bushing dies are good but they dont remove that inside edge, mandrels work but that is another step. Some dies like SAC let you have bushings and mandrels at the same time but thats expensive.

A good rcbs FL die with a bit a rcbs lube or imperial lube on the expander ball will work and a touch with the internal chamfer tool should get you seating pressures much more consistent.

Grizzgup said:

Hello all.

When I go to seat bullets I’m noticing a substantial difference in the amount of force required to seat them. I measured all the case necks and they’re all the same. I’m using forster collet dies with a rock chucker press. I know the best way is to use an electronic press with expanding mandrel dies, but that’s not going to happen anytime soon. I lube all my cases necks with imperial dry neck lube, and am wondering if varying amounts of that can make a difference in the amount of force required to seat the bullets, or if it isn’t a factor at all. I know one of the keys to accuracy is consistent neck tension, and I’m afraid that’s where my hang up is with extreme accuracy. I’m currently shooting just under 1 MOA, but know that several of my guns are capable of more than that.

Click to expand...

After sizing, are the neck outside diameter (OD) pretty much the same - that is, plus or minus .001? Smaller tolerance would be better. If no, then that is a problem you have to solve first, your sizing process is not creating uniform dimensions. If yes (same OD), and you can still feel the difference in the rock chucker (RC) handle then the neck ID varies or - a couple of other things:

• for a given case the neck thickness is consistent but the cases are different from one to another - some .015 some.013 - solution, sort by neck thickness. You will need buttons and a button die to size so that the ID is the same. tool: ball micrometer.
• for a given case, as you measure it at 3 o'clock, 6, 9, and 12 the numbers vary more than about .002 - say 15 15 13 16 - solution, this not good brass, you can't really fix it. tool: ball micrometer
• the top of the necks are consistent but there is a donut at the junction of the neck and the shoulder. They start in easy but you have to push harder to expand that donut - solution, anneal the neck/shoulder, perhaps mandrel, see below.
• the top edge of the case is gnarly and needs to be chamfered - solution, chamfer or trim/chamfer
• the necks have gotten hardened by several firings and they deform elastically when you insert the bullet - seating the bullet does not permanently deform the brass, if you pull the bullet then the neck springs back - solution, anneal the neck/shoulder.

You can also anneal to soften the brass and then use a mandrel to make the neck ID the same. 20th century sells mandrels in .001 steps. You have to anneal first, then size (probably with a button die) to below minimum ID then expand via mandrel to optimum ID. You now have soft necks that will lightly/moderately grip the bullet, all with the same ID, regardless of OD, and because of mandrel, the ID is a cylinder with no donut (more or less) so seating pressure should be approximately the same.