To Size or Not Too Size

1340

1340

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Some people feel virgin brass should be sized before first use.
I recently acquired a Tikka T3x UPR.
For a factory rifle is it even worth it to do that, or just fireform and start reloading?
TIA
 
That depends on manufacture and method of shipping but essentially no it's not needed.
If they are shipped loose they can get banged up and it can effect bullet seating with bent case neck. Always inspect each one. check the flash hole and ensure case length is the same to ensure crimp tension doesn't vary. I use a 21st century expander mandrel on all my cases before loading and have found it to give me much lower SD's Cheers
But if your using high quality brass you will be hard pressed to find variances. Brands like Peterson, ADG and others it's not needed. I still check every one though and run the mandrel.
 
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I've done both ways - when reloading boat tail bullets I let the bullet back end round out the dinged brass. Then that became "too much" when I swapped to flat based bullets - so I started to partial size to get the neck mouths round. Then I discovered that some were taking smidgeon of brass off when cut for length. So those needed chamfering as well. Today I run all through as if previously fired - full length size, trim to length with a Lee trimmer, touch each with an RCBS chamfer tool, then de-grease and load as other cases. Many (but not all) do not get anything trimmed for length, or only part of the mouth does, but they all get touched with the chamfering tool. It strikes me as if modern makers of brass do not know what size it is supposed to be, whereas I trust the reloading gear that I have, to produce the same as I had been using.
 
Peterson Brass says their quality control is high enough that it is not necessary, just chamfer, load and shoot.

They also give you the AMP ##### anneal code for your lot of brass, the h2o volume and other measurement of each lot number.
 
Bump the case mouths into the die enough to true the mouths up, inside case mouth chamfer, do stuff like primer pocket depth, and flash hole deburr(better brass doesn’t need this) and have at it……
 
I always trim/size virgin brass regardless of manufacturer.
Do I need to?
No idea but seemed like a good idea so I stuck with it
 
1340 said:
Some people feel virgin brass should be sized before first use.
I recently acquired a Tikka T3x UPR.
For a factory rifle is it even worth it to do that, or just fireform and start reloading?
TIA
Click to expand...

It very much depends on the brass.

The three Americans, FC, WIN, R.P. I would definitely size.

If you spend a little more and buy Lapua brass, the uniformity will not increase by sizing, Lapua brass is spot on.
 
I would be curious to know if manufacturers resize/trim and chamfer the brass before they load factory ammo ? If not, I don't know why it would be necessary for us.
I personally do not resize or necksize new brass (Lapua, Starline, Hornady), I load it and shoot it (it's just a 100 shot...). But for an event (PRS, F-Open) I do try to use already fireformed brass.

But take note; I do not turn necks or measure pressure when seating bullets etc. I find that I already spend too much time sitting at that bench, life is too short. I like to shoot and at my age I am not planning to become a champion or an ammunition specialist. YMMV
 
All good info, thanks to everyone.
I bought Lapua brass, so checking the flash hole and length wouldn't hurt to do. Mandreling the necks to eliminate dents and to uniform neck tension is also a great idea. Looks like I have some work ahead of me.
 
I tend to run the mandrel though to set the neck tension all the same, so when I reload for the next firing they are the same. Found I don't need to adjust my handloads as much on the 2nd firing.

Heck I've been known to even set the barrel headspace tighter so new brass doesn't have to "fire form" so much. Easy feat with the barrel nut set up.

Even placed 3rd on a marksman challenge with new unfired brass I had loaded up for it.
 
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