New brass prep - expander mandrels or FL with expander?

[satchamo]

So I have 100 new pieces of 243 starline to prep and I went down an internet wormhole and now I’m worried I’m trying to spend money to fix a problem that doesn’t even exist.

Currently I have a forster FL resizer with the little expander ball. I originally thought I’d just run the die through the expander ball without actually pushing the brass up to fully resize but I went down a wormhole last night on expander mandrel dies and now have convinced myself I need the 21st century die and a 241 mandrel to prep all the necks on my new/reloads.

Can I just do my original plan of using my FL die or is it worth it to go the expander mandrel route? It’s worth noting I am pretty OCD about my reloads, even if it “doesn’t make a difference on target” - I like knowing I did everything possible to get it as close to perfect as I could…. So keep that in mind

 

[BBob]

I’m trying to spend money to fix a problem that doesn’t even exist.

Yes you are.

 

[HuntHarder]

I experienced better Es/Sd when I mandrelled. Nothing ground breaking, but i did lower them. Going forward, I will mandrel all my brass. The extra time is not much to me, as I do not shoot 5,000 reloaded rounds a year.

 

[Ganderzone]

Here's my take on it. If you're chasing tight groups, extended brass life, running premium brass Lapua/Peterson/AGD etc then mandrel is the way. If you are reloading once fired Hornady, federal, Winchester and shooting for moa for a hunting rifle stick with the expander ball. I have and use both, my gas guns I use the expander ball and if they shoot .75-1" we are good. My custom rifles that are capable of 1/2" get the full treatment. If I was reloading for a tikka or other factory gun I don't think I'd go through the hassle. All comes down to how much effort do you want to put in for marginal gains. By no means am I saying a mandrel is not worth it, they just have their place.

 

[steelheadmike]

I went through the same exact thought process. I HATED the expander ball on my hornady dies as it had caused me some serious headache. I decap before sizing so I removed the whole ball/spindle and went to the expander mandrel. Not sure it has made any difference but it's less troublesome. Yes, it's one extra step but it's pretty simple and quick.

Use your same FL die, just take out the expander ball.

 

[Vern400]

If you measure your success by the size of your groups, keeping your brass and batches with the same number of firings, annealing regularly, and using a mandrel expander will give you more repeatable results. All it does is provide a more uniform bullet seating Force. You might be able to see a meaningful difference starting at 300 or 400 yards.
You have to be that far out for an unfavorable extreme spread in velocity to be measurable with any statistical confidence. To be honest, many rifles are not good enough to show you improvement for the extra effort.

If you want to make ammunition that's better than what you can buy at the store, custom tailored for your gun, that shoots really good out to 400 or 500 yd. A good quality standard resizing die with the ball expander will be just fine.

Either way, you have to be careful to lubricate inside the neck. There should be little variation in feel of the press effort while expanding necks and seating bullets. If one of them is very soft, or hard and crunchy you might consider setting those aside for a fun shoot or Foulers. It's all about consistency.

 

[Harvey_NW]

Currently I have a forster FL resizer with the little expander ball. I originally thought I’d just run the die through the expander ball without actually pushing the brass up to fully resize

This is all I've ever done with new brass and never had an issue, you'll see more of an effect from the change in dimension of new vs formed brass than anything.

I did a test one time where I had fully prepped brass, some that was loaded for a long time and I had to pull, and 2 different lots of bullets. I reloaded them all and even though there was a drastic difference in seating force, all 10 fell within the expected cone of under 1" at 100 yards.

I seriously wouldn't worry about it or spend a crazy amount of money on branded mandrels, you can order a gage pin on Amazon for $7 and lock it in the RCBS bullet puller collet if you really want to test the idea of mandrels, which is what I'll be doing soon for fun because of @HuntHarder results.

 

[satchamo]

This is all I've ever done with new brass and never had an issue, you'll see more of an effect from the change in dimension of new vs formed brass than anything.

I did a test one time where I had fully prepped brass, some that was loaded for a long time and I had to pull, and 2 different lots of bullets. I reloaded them all and even though there was a drastic difference in seating force, all 10 fell within the expected cone of under 1" at 100 yards.

I seriously wouldn't worry about it or spend a crazy amount of money on branded mandrels, you can order a gage pin on Amazon for $7 and lock it in the RCBS bullet puller collet if you really want to test the idea of mandrels, which is what I'll be doing soon for fun because of @HuntHarder results.

Well I gave into the temptation and went ahead and got one of the 21st century mandrel dies and just kept it simple and got .241 and .222 mandrels for my 243 and 22-250.

Really stupid question- what do you do with the gauge pin? Making a diy mandrel?

 

[SDHNTR]

I just shot this group by doing exactly what you initially were planning on doing. I don’t like extra steps. No mandrel needed.

 

[Harvey_NW]

Well I gave into the temptation and went ahead and got one of the 21st century mandrel dies and just kept it simple and got .241 and .222 mandrels for my 243 and 22-250.

Nothing wrong with testing for yourself, I'm just cheap and try to keep it as simple as possible anymore. HuntHarder posted some data sets in another thread that were valid enough to make me want to test it too.

Really stupid question- what do you do with the gauge pin? Making a diy mandrel?

Not stupid, that's exactly what I'm doing. But I already have a collet bullet puller so I can chuck up a gage pin and run the neck over it, redneck mandrel die . I'll take some emery cloth and steel wool and put a slight taper on the bottom edge of the pin and polish it up for smooth entry.

 

[Castle Rock]

A boat tail bullet is a very efficient expander, new brass gets chamfered, loaded and shot.
If you feel the brass is a bit tight dip the base of the bullet in graphite.