Gunsmithing 1:9 Twist .25WSSM?

[Chris K]

I have a Dedicated Technologies AR in 25 WSSM, its a 1:10 twist 22" stainless ultra match. Love the thing to death, kills everything it hits, shoots .75ish MOA, light enough to be handy, heavy enough to be accurate...on and on.

Recently I have been thinking about having Mike build me an 18 incher with a 1:9 barrel. I've been reading Litz book and going over the stability of bullets. Following the Miller Stability Formula a 1:9 seems to stabilize a broader range of weights and shapes of bullets.

Can a cartridge like a WSSM run from a mid length gas system, and are there disadvantages to 1:9 that I'm not aware of? Most factory rifles I'm aware of in 25-06 or other 257 offerings are 1:10, I assume there is a reason for this, but how would a 9 twist behave in a 25?

Any input?

Thanks!

C_K

 

[blksno]

Re: 1:9 Twist .25WSSM?

I would call Mike. I know he recommends 22" barrels with all his WSSM's but if ANYONE knows what will function, it's him.
The guys been building them for years and probably builds the best ones available.

An adjustable gas block could probably make just about anything work.

 

[2156SMK]

Re: 1:9 Twist .25WSSM?

I would consider doing a 6.5mm on the 25wssm case.
That would get you a better variety of bullets to choose from.
Have you read my write-up on the AR gas system?
www.ar15barrels.com/prod/operation.shtml

I would not recommend a mid-length gas system on a WSSM.
Rifle is where you want to be, even at 18" length.

And listen to Mike, he knows WSSM AR's...

 

[blksno]

Re: 1:9 Twist .25WSSM?

18" barrel and a 15" fft would look pretty sick CK, but if you've already got one 25WSSM that shoots great...what ya want another one for?
I personally don't want one that short, but I'm sure with your skill set, you could get great results with the 6.5 or 30 wssms

 

[Chris K]

Re: 1:9 Twist .25WSSM?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: c_bass16</div><div class="ubbcode-body">I would call Mike. I know he recommends 22" barrels with all his WSSM's but if ANYONE knows what will function, it's him.
The guys been building them for years and probably builds the best ones available.

An adjustable gas block could probably make just about anything work. </div></div>

Been emailing him quite a bit from here. I'm just exploring other opinions...

 

[Chris K]

Re: 1:9 Twist .25WSSM?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: c_bass16</div><div class="ubbcode-body">18" barrel and a 15" fft would look pretty sick CK, but if you've already got one 25WSSM that shoots great...what ya want another one for?
I personally don't want one that short, but I'm sure with your skill set, you could get great results with the 6.5 or 30 wssms</div></div>

For Sarah dude! why else would I need another 25? She likes mine, and I figure I could have a little sister to my other Dtech, build it in more of a DM type rifle. You are reading my mind with the FF tube too...it would look pretty sexy.

It would be a simple "ease of use" type choice, when she hunts we would have the same ammo, similar guns, I can teach her from what I have learned from using my 25, she likes the AR rifle quite a bit (but her favorite is a lever .22 of my dads) and the recoil is extremely manageable. I think its a great lil gun for her (and me

)

C_K

Anything on 1:9? even in bolt guns or other 25's than the WSSM...?

 

[Chris K]

Re: 1:9 Twist .25WSSM?

Quote from the wife when talking about her rifle:

"I'll shoot em dead in the face"

"honey, what if it has antlers?"

"right in balloon knot then."

She's cleanin that one.

C_K

 

[blksno]

Re: 1:9 Twist .25WSSM?

Well that's as good of reason as any to build another one. Never thought of that.
I just can't picture Sarah on a hunt lol, but I'm sure everyone starts somewhere.

 

[Chris K]

Re: 1:9 Twist .25WSSM?

shes not bad, liek a lot of women she sees things before I do...mainly since shes not looking at EVERYTHING like we tend to do, but more looking for anything. It's interesting the way the woman brain works when they are hunting.

C_K

 

[Wild_Bill]

Re: 1:9 Twist .25WSSM?

hi a 9 twist will be fine in your 25wssm especialy if you go with a shorter barrel. if you are using quality projectiles a little extra spin does not hurt. the bigest factor in using the minimum twist comes into shooting military ammo where the projectiles might not be the best quality if you over spin them they can get the wabbles up. i have shot 110gr projectiles and 130's from 308's with no problems at all the 130gr Speer HP projectiles would shoot well under 1/2" at 100 and a 210 can stabalise from the barrel.

Go for it i would also reccomend a rifle length tube with adjustable gas block is you went for a 18" barrel if you have the longer tube it will bleed off more gas pressure as you have to use slower powder int he wssm that a 223 and more of it and the adjustable gas block would let you fine tune it.

 

[Chris K]

Re: 1:9 Twist .25WSSM?

Thanks Bill, now let's see if Mike will build it!

C_K

 

[knockemdown]

Re: 1:9 Twist .25WSSM?

Mike will build you whatever you want

I can tell you that an 18" .25Wizzer WILL be a flamethrower!

Fact is, the shortcoming of any of the Wizzers when wanting to mag feed & launch heavy for caliber bullets is the overall length of the loaded round. You can eeek out a few thou over 2.260" with mag mods & such, but they still have to feed & cycle and may require modding the feed ramps, too...

If you are hell belt on shooting heavies, then I say go for it! I enjoyed my Dtech .25Wizzer and it was a killer. Now I have a Dtech built 1:8" twisted Shilen in .223Wizzer that is a frikken beast as well. However, with some long bullets like the 75gr AMAX, or the VLDs, the magazine constraints of running it over a standard AR-15 lower prevent loading them anywhere close to the lands.
For comparison, a 75gr Amax needs loaded to 2.38" to hit lands, but a 75gr BTHP touchs @ 2.260", so bullet choice is something else to consider in a Wizzer fed AR-15...

In the case of your project, you may want to look into running that upper over Oly Arms' new UMAR lower. The UMAR was designed to run the .22-250 in an AR-15 from proprietary magazines. That extra c.o.a.l. afforded will come in handy if you want to spin big, heavies out of any Wizzer...


OR, if you are just wanting a more handy quarterbore for the little lady, have Mike build you a mid length gassed, 18" .25DTI, like this one...

The DTI is super efficient, very accurate & provides for more than ample smackdown from 31grains of powder. She can shoot the same bullets as you , but you'll need a set of dies to neck down the 6.8 brass...

 

[Chris K]

Re: 1:9 Twist .25WSSM?

The more and more I think about this, the more and more Mike and you guys are right...the DTI might be the best choice. As much as I want to fight it, its becoming a losing fight.

I need to talk to mike and see how far he's backed up and then choose. The wife may just inherit my 25 and pave the way for me building something for me. I have plenty of time left over here to figure it out and make a choice I guess.

Thanks guys,

C_K