6.5 SLR/S Improved - Ready for testing

[Rockfish Dave]

Well I just got back my chambered barrel.

I've processed a 100 cases for testing. I had deburred the flash holes, uniformed the primer pockets, chamfered the necks and annealed after sizing.

I used the Frankford Arsenal OAL Gauge and came up to similar measurements as posted on his website.

So how is mine "improved" (highly subjective since it is not tested)? I changed the dimensions to blow out some of the taper. I decided to try this since my 284 Shehane has worked so well, I figured why not try it on this as well?

The down side is 2 sets of Sizing dies.

My only concern is the extraction. If it extracts fine then I'm a happy camper. If it does not then I just sank a ton of $ just to learn one way not to do it.

 

[Rockfish Dave]

Forgot to add details on the test platform:

Surgeon 591R
McRee Chassis
Bartlien SS gain twist starting at 1:8.75 ending in 1:8, 26" finished length.
Jewel Trigger
Vortex Razor 5-20 HD/Vortex Rings/Vortex Level

That pretty much sums it up. I'm hoping this isn't a colossal mess.

 

[22BRGUY]

Thanks for info Dave...I'm interested in your project as I've been looking at the 6.5 SLR for awhile now. The shoulder on the standard SLR is 30 degrees, my understanding....approximately what angle do you think will be on your improved? and what loads/powder/bullet combo are you trying? Thanks much and Best Wishes

 

[Rockfish Dave]

I said "improved" because it is slightly changed. I changed only the taper of the case, similar to the Shehane modifications to the 284 win case.

The shoulder remains the 30 degree of the original 6.5 Super LR/S.

Powder is: H4350
Bullet is: Lapua 139 gr Scenar
Brass is: 243WIN
Primer is: CCI BR2


For fire forming loads (reduced loads) I have the following in .2 grain increments:
Starting loads 40.2gr
Ending Loads 41.0gr

 

[22BRGUY]

Thanks Dave...Will be watching for your results.Gotta ask though how or what you feel would be the benefit to this?? (forgive my ignorance)

 

[Rockfish Dave]

Why do it?

For a little more capacity; since I would be losing a little capacity with the 6.5 SLR/S resizing.

I am hoping that the larger case capacity will allow lower pressures to get the same velocity and a little better case life.

With the full power fire formed loads I hope to get around 3,000 fps. I may be overly optimistic, but part of the fun is finding out.

As much as it was of: 'If I am going to do a wildcat, why not go all in?'

Is it worth it? That is subjective.

I really like my 284 Shehane and have no regrets. If this performs incrementally better as the Shehane does, then for me it will be worth it.

 

[22BRGUY]

Thanks, sounds like fun for sure.

 

[Rockfish Dave]

Just got to fire form one case and thought I'd post some comparative photo's

260REM-243WIN-6.5SLR-6.5SLR Imp


260REM-243WIN-6.5SLR-6.5SLR Imp


6.5SLR-6.5SLR Imp


6.5SLR-6.5SLR Improved

 

[Rockfish Dave]

Comparison of the reamer prints:

6.5 SLR-Improved:


Original 6.5 SLR/S:

 

[22BRGUY]

Great pics and info Dave...really like the looks of that case. How soon before some testing do you think??? Will be waiting for results for sure. Thanks again

 

[Erik Cortina]

The down side is 2 sets of Sizing dies.

Why do you need two sets?

 

[Rockfish Dave]

Great pics and info Dave...really like the looks of that case. How soon before some testing do you think??? Will be waiting for results for sure. Thanks again

Intended to do the initial fire-forming testing and barrel break in yesterday but ran out of time. I'll try again next Sat.

I only was able to shoot one round. Extracted easily, and when I measured the case it came in at the full fire formed dimensions. The round was with a 40.2 grain charge of H4350. The velocity was 2616fps, which really does not mean anything given that it was only one shot on a new barrel.

 

[Rockfish Dave]

Why do you need two sets?

The SLR dies is for the first sizing before fire forming. The second set of dies is for the fire formed cases since I blew out the taper on my version.

The last picture of the case comparison series shows the change in taper the best.

 

[Raythemanroe]

I want to know your findings on the speeds your getting!

 

[22BRGUY]

I want to know your findings on the speeds your getting!

Me too!

 

[Erik Cortina]

Why do you need two sets?

The SLR dies is for the first sizing before fire forming. The second set of dies is for the fire formed cases since I blew out the taper on my version.

Can't you do the initial operation with the second set of dies? All you are changing on the first operation is the shoulder angle aren't you?

 

[Rockfish Dave]

Can't you do the initial operation with the second set of dies? All you are changing on the first operation is the shoulder angle aren't you?

That is a good question, and the answer is no you cannot. I tried it and without the support on the case wall the pressure of changing the shoulder collapses the cases. Again, I know because I tried it out of curiosity and that was the result.

Once the first sizing is done the original SLR FL sizing die is no longer needed, unless prepping new brass.

I bought my Improved dies from Whidden Gunworks. Very fast and all I needed to provide them was the reamer print. I actually received those dies faster than the SLR dies I bought from Mr. Whitley.

If I had to do it again I'd just order both FL dies from Whidden and one bullet seating die based off of my reamer print and be done with it.

Websites mentioned above:
http://whiddengunworks.net/reloadingdies.html
http://6mmar.com/65_SuperLR.php

 

[Erik Cortina]

Can't you do the initial operation with the second set of dies? All you are changing on the first operation is the shoulder angle aren't you?

That is a good question, and the answer is no you cannot. I tried it and without the support on the case wall the pressure of changing the shoulder collapses the cases. Again, I know because I tried it out of curiosity and that was the result.

Once the first sizing is done the original SLR FL sizing die is no longer needed, unless prepping new brass.

I bought my Improved dies from Whidden Gunworks. Very fast and all I needed to provide them was the reamer print. I actually received those dies faster than the SLR dies I bought from Mr. Whitley.

If I had to do it again I'd just order both FL dies from Whidden and one bullet seating die based off of my reamer print and be done with it.

Websites mentioned above:
http://whiddengunworks.net/reloadingdies.html
http://6mmar.com/65_SuperLR.php

Makes sense. I played with a wildcat where the shoulder had to be pushed back, and I found annealing before pushing shoulder back was beneficial. Either way it's fun playing with wildcats. Have fun!

 

[Rockfish Dave]

Makes sense. I played with a wildcat where the shoulder had to be pushed back, and I found annealing before pushing shoulder back was beneficial. Either way it's fun playing with wildcats. Have fun!

Thanks for the tip, I'll do the annealing first on the next batch.

 

[Rockfish Dave]

Finally shot the first 25 rounds and all I can say is WOW. Worst five shot group was 1/2 moa, second worst 1/4 moa and the rest one hole groups (excluding the first cold bore).

To say I'm happy would be an under statement!

Bartlien spun up a heck of a barrel!

I'll post pics of post fired brass and the groups after running them through the measurement software and the chronograph results (not too happy about those, but may change after the initial fire forming rounds).