.338 Whisper #2 in HK91 platform?

[avenger15]

Do you think it's feasible? I'm debating whether to go this route or buy an AR-10 conversion from SSK. However, I am not knowledgeable enough about the HK operating system to know whether it would be doomed from the start.

I'd love to have something like an HK51SD, but in a Whisper caliber.

[THE DOCTOR]

I doubt you could generate sufficient pressure in a 91 platform to make the rollers unlock with a subsonic cartridge(not sure but i assume that is what you are going for) maybe with a lightened mainspring maybe......?

Would be easier to do this project not that it would be easy on an HK anyway on a HK 93 that way you wouldn't have to weld the bolt face up to make it 338 whisper #2 that has the 221 fireball or 223 shortened the 93 would already be the right diameter.

Would be cheaper and easier on the ar platform for sure

but more unique on the HK

only you can decide if it is worth the hassle.

[avenger15]

I see what you are saying there about the 93, I was originally considering .300 Whisper through a Vector 53 clone I own, and might still go with that project for simplicity's sake.

[THE DOCTOR]

anything is possible if money is no object. do you want to integrally suppress it like the one in your picture or just put a can on the end of a 30 cal rebarreled 53?

[avenger15]

Doc, I already own a detachable 9mm can from an HK-94 converted by Ceiner into an MP5SD. I've been in contact with a guy over at HKPro.com who built his own 53SD, so maybe that project will pan out. From there, it would be relatively simple (I hope) to convert to .300 Whisper and then to expiriment with the right load for the round.

[THE DOCTOR]

in theory it should be simple but getting a fluted chamber like the 93 for a 338 will likely be difficult and achieving enough pressure to unlock the rollers will be a big hill to climb. trimming the mainspring can only go so far because it will not want to rechamber a new round just like the ar

i am running a wolff lightened spring on my ar and it works great

You might get wolff to make you a custom spring nice guy there would be worth a try

again I wish you lots of luck