Roberts 260 with the 30 degree shoulder??

[Raptor]

Robert or anyone shooting one of these. I have a question on forming the brass. I have a 6SLR that you run the brass into the SLR die and then you fire it and you have your case. The nice thing about the 6SLR is that it shoots as fast and as well fireforming the brass as it does with formed brass. Plus you can do load development while forming the brass.

Now my question... Is the 260x30degree the same way?? Do you form the brass in the die first?? Or do you use a stock 260 and fire it in the chamber to get your brass??

If its the latter I may not be intrested in one because I hate fireforming 300rds of brass its such a waste of barrel and bullets then you have to do all your load development AFTER your brass is formed. You can wind up with 500rds down the barrel before you start shooting matches. Thanks guys!!!!!!

 

[rcw3]

Raptor

Stick a loaded 260 Rem round in the 260 Imp 30Ëšchamber and pull the trigger - done - brass is formed - -

BUT

Fire forming loads can be very very accurate - so there is no need to always pre-form brass. In fact with the barrel I have on my prone gun I would not hesitate to shoot a 600 yard match with fire forming loads.

Here's an example of a 10 shot group I shot prone at 100 yards (i.e. not off the bench, just a shooting jacket and a sling). The load was 42 gr of H4350, new Lapua 260 Rem brass, BR-2 primers and Sierra 142's - - deadly accurate!

I really like that 6.5 mm cartridge especially for running the 139-142 gr class of bullets. Smaller cartridges like the 6.5 Creedmoor are good but I think they are really best with the bullets in the 120-130 gr range and they tend to labor more to run the bigger projectiles.

I just put up some more chrono data on the 260 Imp 30Ëšcartridge out of a 26" barrel - - you can view it here:
http://www.6mmar.com/260_Imp_30_.php

Robert
AR-X Enterprises LLC
www.6mmAR.com

 

[Raptor]

Thanks for the reply Robert!! Do your have or know what velocity your getting when fireforming the case??? I will be building a 26" rifle. Thanks again!!

 

[rcw3]

The fire forming loads seemed to run about 50 fps faster than the same loads with formed brass. I also ran fire forming loads with 43.5 gr of H4350 with the 142's and that was just as accurate as the 42 gr. load. Chrono results are on the web page.

Robert

 

[BradY]

Thanks for the info Robert- my reamer hopefully isnt too far away and action, barrel block and stock have been sourced for my build. Barrel should be here in a couple of weeks. Then I have the fun process of waiting for permits (stoopid aussie gun laws)

I was going to run in with 120SMK's as I have a heap- do you have a suggestion on a charge for them? Planning on trying lapua palma cases neck down and turned and CCI450 primers. Have varget and 4350 to use.

 

[Raptor]

Robert, am I reading you post wrong?? You stated that the fireforming loads are "Faster" than the actual loads in the formed case?? Isn't it usually the other way around???

Can you do your load development fireforming or does that not work out to well?? Thanks again for all your help and your great cartridges!!!

 

[BradY]

Raptor that would make sense as 45gr in a standard case would produce more pressure than in the improved case as it would take up more case capacity.

Also you could do load development for an accurate fireforming load to use but I wouldnt be trying to do final load work in anything but cases that are formed. Otherwise you add a variable that isnt consistent to the equation and your looking for consistent results at the end of the day.

 

[rcw3]

Raptor

With all other things being equal, if you shoot a fire forming load with a certain powder charge vs a formed case load with the same powder charge, the fire forming load will typically be faster (at least that's what I have seen with chrono results). I suspect it relates to the fact that the fire forming load starts out with a smaller capacity case, and even though it blows out in fire forming, it somehow causes the powder charge involved to build a different pressure curve that yields more velocity (at least that's my theory on that).

I have always found that if I worked up a fire forming load that was accurate, it also worked well in formed cases, but that does not mean you cannot find a heftier load with formed brass that will perform well too.

Robert

 

[Raptor]

Thanks Robert and BY1983 that makes sence. I guess I got the notion from forming my 6BRX brass. My loads for fireforming were always a couple of minutes low at 600yds. from my formed loads but as I now think about it there was 3grs less powder in the fireforming load too!!

Once again thank you for your time and help!! I will be ordering my reamer tomorrow. I am looking forward to trying out this round. I only hope it will shoot as well as the 6SLR does!!