6.5x55 SLR

[chalkeye]

Guys, as I've already stated, I'm trying to work out if this is possible WITHOUT fireforming. AI is out for this reason.

Lapua brass would make me choose x55 brass over x57 brass to wildcat.

Agreed, but I don't think I can push the shoulder of x55 brass out enough to remove the taper - without fireforming. 6.5-284 brass could work (and comes in Lapua flavour) but I just don't know if it's technically possible to push a shoulder back that far.

 

[1shot]

Guys, as I've already stated, I'm trying to work out if this is possible WITHOUT fireforming. AI is out for this reason.


Agreed, but I don't think I can push the shoulder of x55 brass out enough to remove the taper - without fireforming. 6.5-284 brass could work (and comes in Lapua flavour) but I just don't know if it's technically possible to push a shoulder back that far.

Every time you size and press the trigger, you fireform.
Not in the way we think of "fireforming" one cartridge to another or improving it, but the brass moves none the less.
I have personally watched a 6.5x55 Swede get "fireformed to the GWI at the NRA Nationals at the 800 yd. line that was a clean. No loss of accuracy that day!
I hope this helps,

Lloyd

 

[kyreloader]

Every time you size and press the trigger, you fireform.
Not in the way we think of "fireforming" one cartridge to another or improving it, but the brass moves none the less.
I have personally watched a 6.5x55 Swede get "fireformed to the GWI at the NRA Nationals at the 800 yd. line that was a clean. No loss of accuracy that day!
I hope this helps,

Lloyd

I echo this thought.

I have killed two whitetails now "fireforming" my 6.5x55 Swede into BJAI and shot HM scores at Midrange Fclass matches "fireforming" cases.

 

[chalkeye]

I don't know what to say. Unless you can help with information about how far you can push case shoulders back with a die, please refrain from posting.

 

[rardoin]

I push the shoulder of .308 Win back 0.040" while forming them into 6.5 Creedmoor. I have formed at least 400 cases with no loss from case/shoulder collapse. I think your idea is do able. I would take some of the taper out of the case as suggested.

Kyreloader...I sent you a PM

 

[chalkeye]

I push the shoulder of .308 Win back 0.040" while forming them into 6.5 Creedmoor. I have formed at least 400 cases with no loss from case/shoulder collapse. I think your idea is do able. I would take some of the taper out of the case as suggested.

Fantastic, thank you!
Did you do it in one operation, or several?
Did you have any issues with neck thickness - donut, etc?

 

[rardoin]

I sized down about 60% of setback with a 7mm-'08 die with the expander ball removed, trimmed the neck about 0.060" (the case mouth had a trumpet flare), setback the shoulder to Creedmoor spec with a FL bushing die sans bushing, then with bushing, trimmed to final length, annealed, expanded neck to match turning mandrel interference, turned necks (0.018" after operations so turning was required) and fire formed. The case volume pre-firing was about 48.9 and after first firing was 49.8gr water. I use lanolin lube. When I size down in the first step I run the case in the die with 3-4 strokes of increasing throw to sequentially size it and turn the case about 1/3 revolution between strokes. I never lost a case or stuck a case with this process. Any doughnuts are pushed out with the expander mandrel and taken off the OD of the neck. Without annealing I would expect some springback of the doughnut but I expect my lack is due to annealing in the process.

 

[kyreloader]

I don't know what to say. Unless you can help with information about how far you can push case shoulders back with a die, please refrain from posting.

Sorry.

I went the 6 SLR route and did not see the benefit. Yes, I was able to form the case with a die, but, I still had to fire the case because the shoulder was not fully formed but more rounded in appearance. That firing was useful but did not/could not use full-house loads.

I see the same with the fireforming needed to go the AI or BJAI route.

I will bow out of this thread, sorry if I detracted from it's content.

 

[chalkeye]

I went the 6 SLR route and did not see the benefit. Yes, I was able to form the case with a die, but, I still had to fire the case because the shoulder was not fully formed but more rounded in appearance. That firing was useful but did not/could not use full-house loads.

Thanks, that's useful information!

Why couldn't you use full loads? Case capacity? How much did the case change after firing?

 

[kyreloader]

Thanks, that's useful information!

Why couldn't you use full loads? Case capacity? How much did the case change after firing?

It wasn't the loss of case capacity, it was the change in capacity between cases. You would have a case that looked perfect, then a case that had a rounded shoulder, then a normal, then two with rounded shoulders. I guess there was enough difference in metallurgy between the cases that all would not form uniformly. After firing, all the cases looked the same and the differences in the case capacity between the cases was minimized. Shooting cases formed by the die, I had trouble getting my ES during a string to be low enough that I did not have significant vertical during 600 yard Midrange matches. After shooting the first time, I could then used known loads and the vertical was alleviated.

The load that I used for the first firing was 43.5g H4831SC (a known node with 105s) and it shot reasonable. My fireformed load was 45.1g and it shot great at that node.

To me, using the die to form cases like the SLR, looks and shot similar to my experience with hydroformed Dasher cases. Close, but enough differences in internal case capacity that it would/will show up on target at 600 yards.

So, my choice to go with BJAI was knowing that I could shoot known match factory loads from Lapua for midrange club matches to fireform or to load known 6.5x55 Swede loads with Lapua brass with consistent internal capacity and not have the vertical problems that I was having with the SLR first firing. I guess I didn't want to waste my barrel life simply fireforming.

Hope that helps.

 

[chalkeye]

Great detail, thanks - I wonder if anyone else has had similar experience with SLR cartridges?