Fireforming Cases

[SlightlyDistracting]

So I have a stupid amount of 22-250 brass. I decided I was going to try forminga few cases into brass for my 6.5 creedmoor. More just to try it out. Read about guys having a lot of success with 22-250 cases.
Ive made 25-06 cases with extremely good results.
The parent case for the creedmoor is the .30 Tc and that is the same case as a 250 savage or 22-250.
After sizing the brass with my 65 creedmoor dies I noticed a lot of differences. The sizing worked very well.
My question is does the different rim types ( seen in pic) matter? They do chamber in my rifle. Will fireforming blow them out to fit my chamber. They seem durastically different.
The case on the left is an unfired nosler 6.5 creedmoor case and the right is the 22-250 case worked in a 65 creedmoor full length die

[SlightlyDistracting]

I like the idea of using the 22-250 brass because it seems my necks are not getting too thick since none of the brass from the shoulder is being turned into neck. Seems more ideal than using longer cases and necking down??

[Full Curl Earl]

I'm no expert on fire forming that specific case, but am curious if they chamber in your rifle as is? The extractor grooves are definately different.

[elkhunter11]

Extractor grooves vary in appearance from brand to brand in the same chambering.

[SlightlyDistracting]

Originally Posted by elkhunter11

The extractor grooves vary in appearance among different brands of the same cartridge.

Thank you. This is what I was wondering.

[SlightlyDistracting]

Originally Posted by Full Curl Earl

I'm no expert on fire forming that specific case, but am curious if they chamber in your rifle as is? The extractor grooves are definately different.

They chamber and extract very nicely.

[SlightlyDistracting]

Will firing them blow them out that much? With my 25-06 I was necking down 30-06. They seemed closer even before firing them

[SlightlyDistracting]

I think I may just live with my over abundance of brass and order some more nosler in 65 creedmoor. Lol

[260 Rem]

I have no experience with the two cases, but would guess the extractor groove profiles will change very little, if at all? I would also guess it would require a stout load to blow the taper out of the 22-250 case in one step...and sometimes, requiring more than one step results in inconsistencies. I also wonder when the taper straightens, if the neck length will shrink a little?

[SlightlyDistracting]

Ive read that most guys find the length to be jussst under spec after firing. Obviously depending on the starting length
Im watching videos right now of guys fireforming a 280ai
Im shocked how much he blows out the shoulder
Hes actually using cream of wheat on top his powder. Lol
But it works. The end result is a beautiful case

[260 Rem]

Reduces throat erosion by a few shots....saves a few bucks. Smells like burned cereal.

[SlightlyDistracting]

Originally Posted by 260 Rem

Reduces throat erosion by a few shots....saves a few bucks. Smells like burned cereal.

Right? Makes sense. Lol

[Pathfinder76]

You need to control headspace somehow. Are you moving the shoulder in the sizing die?

[bubba300]

I have done it with the 22-250 case and found it better to just fireform them and not run them threw the sizing die,it keeps the neck longer.I used a 308 sizer stem a little on the neck of them to hold them in the chamber better.
I have a rcbs pricision mic gauge and worked up to 18 grs of unique and cow before it put the shoulder where it was supposed to be,not telling you to start at 18 grs as every rifle is different.I used remington cases.