Mrodair SPA M10 big bore conversion...

[Stikman]

Hey all, considering doing a .257 conversion on this rifle, has anyone done a big bore conversion on this platform. If so, did you do any valve or performance mods to get where you desired?

Also, any long term rifle performance observations would be appreciated.

Thanks...

Gene

[Motorhead]

Few guys have done big bores or converted PCP's to larger calibers.  Indeed valve and transfer mods are going to be required as the weight of projectile and power wanted from it increase.

.257 caliber best I understand is a SLUG caliber so weight will be a pretty substantial change from rifle being a pellet weight shooter in stock form.

[PakProtector]

Load up two King Heavies...see where that gets you. That is nearly 70 gr ov projectile, typical of what you might find in .257.
cheers,
Douglas