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new barrel, wrong twist?

I received a new 6mm barrel yesterday from a well known premium (button) barrel maker.

I ordered a 1:8 twist, and it measures out to roughly 1:8.25.

I want to shoot the 105-108 range target bullets (in a 6mm BRX). I do not intend to shoot the 115s.

Do I have a problem?

I don't want to take the time and expense of having if chambered it if it's going to be borderline too slow. Thanks in advance.

-nosualc
 
No, it won't be a problem. You'll even be able to shoot Berger's new hybrid 105, anywhere but sea level & cold. 115s probably wouldn't be a problem either.

It is sad though that so many barrelmakers don't even bother to notice what they're actually making and sending out to shooters.. Even worse that so many shooters and sites representing them let it fly.
Unless in a hurry, I would send it back to the barrelmaker, ask them to pay attention with the next barrel, and verify that it's correct as ordered.
I once did this 3 times with a Schneider, as they just couldn't get anything right.
 
nosualc said:
I received a new 6mm barrel yesterday from a well known premium (button) barrel maker. I ordered a 1:8 twist, and it measures out to roughly 1:8.25.

Not to light any fuses here... given your adjective 'roughly' how did you determine that barrel's slower than 1:8?

Have you contacted the manufacturer?

As we no nothing at all about your tolerance for accuracy or the type of shooting you intend to do with this barrel (BRX I assume you shoot long range?) it's risky to say whether it'll meet - or even exceed - your expectations. One manufacturer whose 105 grain 6mm bullet I shoot a lot of recommends a minimum 1:8 & as such one barrel I use for 1,000 yards is a 1:7.8.

If you limit your choice in bullets to nothing over, say 100 grains, you might be OK but then why compromise? See what the manufacturer has to say on this & get back to us please.
 
Another consideration is how was the 8.25 twist measured? If it was taken with a tight fitting patch, it may give you a reading that is very close, but without the use of a special tool, ( discussed on this site earlier), you may in fact have a 1-8. I've always thought of the patch method as approximate, but even at that I just go out & shoot the thing & determine which selection of bullets do the best.
 
Not sure if anyone else has had the same results but using the patch method on a couple of my barrels resulted in a variable of 1/4 inch or so.
 
Sorry, I was trying to keep my original post rather brief and to the point. I'll elaborate further.

My methodology for measuring twist was as follows:

Take a clean, tight fitting patch on a jag, insert it about 1/3 down the length of the barrel. Put a piece of masking tape on the cleaning rod at the very edge of the barrel. Index the cleaning rod where it meets the rotating handle with a sharpie. Push the rod in further until the index marks line up again, being very careful not to change the position of the handle. Put another piece of masking tape on the cleaning rod at the very edge of the barrel. Push the patch out the end of the barrel, remove the cleaning rod, and measure between the two leading edges of the masking tape.

I did this 5 times and was within 1/8" each time (always actually over 8.25"). I've used the same methodology on other barrels (and did so again today), and they measured where advertised. I know this is not a super precise way of measuring things (hence the word "roughly"), but consistent enough that I'm sure it's slower than 1:8.

I have not contacted the manufacturer yet. I was trying to figure out if this is an issue worthy of a fuss before doing so. If bullets in the range I mentioned in my original post will work well with a 1:8.25 twist, then I'm happy. The barrel "looks" great with a bore scope (which doesn't mean much I know, but I'm optimistic).

I am building a f-class rifle to be used at 600 yards primarily, 1000 yards occasionally.

-nosualc
 
nosualc said:
I am building a f-class rifle to be used at 600 yards primarily, 1000 yards occasionally.

What's your preference among the various 105-108 grain bullets available?

Even before Berger announced their new 6mm 105 Hybrid the selection includes many proven performers. Give a mind to stability factor (eight described in Brian Litz's 2nd edition range from nominal 1.43 to 1.69 in 1:8, all good) for the temperatures you typically shoot in when making your selection.

As long as it's a quality barrel & chambered responsibly it ought to shoot just fine with the right bullet for the twist & conditions.
 
spclark said:
What's your preference among the various 105-108 grain bullets available?

Even before Berger announced their new 6mm 105 Hybrid the selection includes many proven performers. Give a mind to stability factor (eight described in Brian Litz's 2nd edition range from nominal 1.43 to 1.69 in 1:8, all good) for the temperatures you typically shoot in when making your selection.

As long as it's a quality barrel & chambered responsibly it ought to shoot just fine with the right bullet for the twist & conditions.

My preference is for whatever shoots the best. ;) We'll see.

I'll probably start with the Berger 105 VLD and the 107 SMK. The Berger 105 Hybrid may go to the top of the list if reports and availability are good (I expect yay on the former, nay on the latter for a while). The 105 AMAX is also tempting.

I'll look in Litz's 2nd edition tonight when I get home.

-nosualc
 
nosualc said:
My preference is for whatever shoots the best. ;) We'll see. I'll probably start with the Berger 105 VLD and the 107 SMK.

My standards, in that order. Tried some Lapua 105's @ 600 yards when my supply of Bergers ran low a couple of weeks ago, was pleasantly surprised.

Good luck & good shooting! Please update us all once you get some rounds thru your new build.
 
Nosualc
We are using 8.5 twist barrels with the bullets you mentioned and are getting great results.
Lynn
 
My standards, in that order. Tried some Lapua 105's @ 600 yards when my supply of Bergers ran low a couple of weeks ago, was pleasantly surprised.

I have tried Scenar's in three of my rifles within the last 6 weeks. I can definetly state the above as well.

105's in my 6br, 6brx, and my 6x47Lapua, 123's in my 6.5x47L.

The only problem I have . . . I don't know which one to shoot now! All the above will cloverleaf with the Scenar's! JLK's came in second just for the record!
 
I spoke with the barrel manufacturer yesterday, and he assured me that the 1:8.25 twist was intentional, and that for the bullets mentioned that this is optimal.

I find it a odd that when I ordered the barrel this was never mentioned, and that the website and the invoice all specify '8'. I'm an engineer by trade and to me, 8 means 8.0, not 8.25. Seems a little sloppy for somebody in their line of work to be so cavalier with their numbers. Or duplicitous. Lesson learned for me; the next time, I will be more specific.

From the feedback y'all have given, and a little bit of suggested reading, I'm sure that none of this will matter. The original question has been answered. Thanks for the help guys!

-nosualc
 
I read about some guy that make a machine to test barrel twist.
He found that twist varied some from what was advertized.

Hal
 
Dont the Kreiger gain twist barrels finish at 8.25"?

I couldnt get 115s to work in my 8" twist barrels, but these were slightly slower than 8" like you found, both button rifled. Both loved the 105gn class bullets though.
 

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