Gunplummer

6.5x55 (Re-cut Arisaka), 6.5x50 (Arisaka), .260 Remington (99 Savage), 6.5 Carcano. Killed deer with all of them. May put a 6.5x57 together if I get time.

8mm/06

Gunplummer,

Did you have any trouble with the Arisaka to 6.5 X 55? I'm considering this but would love to hear of any issues or trouble this conversion created. If you don't post bakc here I'll try a private message to you.

I see possible extractor issues, maybe magazine overall length restricting the loads of the 6.5 X 55 to 140 grainers or less without opening up the mag well .....

thanks

salukipv1

6.5mm Rem.Mag. 120gr core lokts

used it on 1 antelope hunt. have since sold the scope that was on it, need to put a new one on it.

Ridge Runner

the Gibbs uses a 270 win. case, its kind of a pain to make cases for, you size a 270 win. case in the 6.5 gibbs die to a crush fit in the chamber, then you prime and charge with 11 gr of unique, tap the case to level the powder, fill it with cornmeal right up to the top of the case mouth, put your finger over it and tap it on a table to settle it, roll up a piece of paper towel into a worm, pack it into the case mouth then use a punch to push it in tight.
now remove the brake, tilt the barrel downward and chamber the round and fireform it, watch the barrel heat cause it will get hot, cases come out about 95% formed, the rounded shoulders will sharpen up the first full power load ya fire through that case, oh and ya lose 2% from split necks.
a 270 beside the 6.5 gibbs
easiest way to make 6.5/06 AI cases, prime new 2506 cases, add a top level 6.5/06 AI powder charge, seat the proper weight .264 boattail bullet for the charge, shoot it.
a friend just rebuilt his 6.5 Gibbs, he said it had 2500 rounds through it.
RR

emtrescue6

I'm guessing there is a small step RR forgot to mention...you need to expand the neck on the 2506 case to .264 using an expander ball from a die to allow for seating the .264 boooolet....

My experience with the 1 Ackley I have (257 Bob AI), which is new to me...is that best performance comes from fireforming with heavier/longer bullets that you can jam into the lands helps ensure a good formed case and prevents the firing pin from striking the primer just enough to allow the round to travel forward slightly when fired. I have formed just short of 50 Remington cases to date and have had no loss due to cracked necks....so far! If I can fireform an AI successfully my first try, anyone can....LOL

Ridge Runner

nope ya don't, the brass will easily stretch .007 with the help of the boattail bullet
ackley cartridges headspace .004" shorter than the parent case so you do not have to jam them, they are jammed on the datem line or whatever they call the line where the neck contacts the chamber.
The gibbs cracks necks (actualy it splits the shoulder) because not only are you changing the shoulder to 35 degrees, your also moving it foreward about 1/8th". it also doesn't show great accuracy with fireform loads like the AI cartridges, thats why I don't fireform for it with bullets, no use wearing a barrel out with mediocre velocity and accuracy.
see the case on the far left, see the split in the shoulder?

RR

Mojotex

6.5x55 SE Deer and feral hogs.

emtrescue6

Good point on seating a .264 bullet in a .257 case with a boattail, that obviously was lost on me.

You may very well be right on the fireforming of AI cases not requiring the "jaming" into the lands when forming from the parent case...this is my first AI and my smith and several friends that have them advised doing so to ensure a good fire form and reduce loss from split necks. I have yet to experiene any case loss using the "jamming" processs with heavier bullets...I have witnessed such "loss" watching others fireform...I am sure my day will come.

As always, thanks for your input RR

jerry d

Rumor has it that Remington is chambering the SPS in .260 with an 8 twist barrel for 2014.

Ridge Runner

EMT, that's the reason you can just use factory ammo to make brass for an AI, it's also why when rechambering a standard cartridge to an AI you must set the barrel back, to set the headspace .004" shorter than the parent.
Using factory ammo to fire form you may have slightly rounded shoulders, but that don't hurt a thing, doesn't affect accuracy and they'll sharpen up nicely the first full power AI load ya shoot through them.
RR