I was gifted a Remington 40x with a 6.5-08 WTC barrel and Enertl 16 scope. My father-in-law was a Master Long Range competitor and went to Perry and Quantico with it every year and won numerous awards with it around the Pittsburgh tristate area. He told me to rebarrel it as it was a odd wildcat cartridge he developed custom loads for over years, and said it would not chamber a standard .260 Remington round. I have the .260 and custom 6.5-08 dies for it along with 7mm-08 and .308 dies. I have an abundance of .308 case both military and commercial. I will probably stick with the lighter commercial cases. I load strictly military 5.56, 7.62 and 30.06 as I am mainly a CMP/HighPower shooter and not much more experienced outside of mindlessly loading military cartridges for service rifle competition.
Using this data:
https://loaddata.com/Cartridge/65-08-A-Square-Data/6074
I took a fired range Federal .308 Win commercial case and sized it with the .308 dies then the 7mm-08 sizing die, then I sized again with the custom 6.5-08 die, I then trimmed it to the recommended trim to length of 2.005", I seated a 142 grain SMK 6.5 bullet to a coal of 2.8. I put in in the breech of the 40x and the bolt easily chambered without resistance in the chamber. I checked it with a .260 case checker and I could see the neck was below the case length hole. A .260 has a case length of 2.035 with a 2.015 trim length.
With the googling of the best case forming data I churned up this is what I crafted from fired range .308 brass. Th other option was to use .243 brass. Does this sound right/safe?
I am going to call Sierra next but I guess I follow standard .260 Remington load data for 6.5mm 142 grain SMK bullets with IMR 4350 the powder he made all his test/comp loads with a winchester 9 1/2 primer which he gave me 2 kegs, and thousands of bullets and primers but no cases. I have a gunsmith that can bore a new chamber in 6.5 Creedmore or 6.5-284 Norma but he said that latter round would burn up barrels in rapid fashion. As long as I know what I am doing I am content with using the 6.5-08 round. I plan to shoot F Class 300+ matches with it and the load I work up.
https://load-data.nosler.com/load-data/65-06-a-square/
Using this data:
https://loaddata.com/Cartridge/65-08-A-Square-Data/6074
I took a fired range Federal .308 Win commercial case and sized it with the .308 dies then the 7mm-08 sizing die, then I sized again with the custom 6.5-08 die, I then trimmed it to the recommended trim to length of 2.005", I seated a 142 grain SMK 6.5 bullet to a coal of 2.8. I put in in the breech of the 40x and the bolt easily chambered without resistance in the chamber. I checked it with a .260 case checker and I could see the neck was below the case length hole. A .260 has a case length of 2.035 with a 2.015 trim length.
With the googling of the best case forming data I churned up this is what I crafted from fired range .308 brass. Th other option was to use .243 brass. Does this sound right/safe?
I am going to call Sierra next but I guess I follow standard .260 Remington load data for 6.5mm 142 grain SMK bullets with IMR 4350 the powder he made all his test/comp loads with a winchester 9 1/2 primer which he gave me 2 kegs, and thousands of bullets and primers but no cases. I have a gunsmith that can bore a new chamber in 6.5 Creedmore or 6.5-284 Norma but he said that latter round would burn up barrels in rapid fashion. As long as I know what I am doing I am content with using the 6.5-08 round. I plan to shoot F Class 300+ matches with it and the load I work up.
https://load-data.nosler.com/load-data/65-06-a-square/