3 groove barrels-mullerworks

[potatoe]

Hey fellas, I'm looking for some input on some 3 groove barrels, more specifically the mullerworks. I've never had one and they seem to be less used than the 4 or 5's. Whats some pros/cons?

 

[JRS]

You might be better served by moving this to the gear talk heading.

 

[KMart]

Here is a discussion on 3 groove barrels from 2010 (main message board). Quite a few opinions here.
http://forum.accurateshooter.com/index.php?topic=3745922.msg35853542#msg35853542

 

[jfseaman]

I don't know Mullerworks but my 3 groove Pac-Nors work very well.

Mullerworks is the first barrel I've found for my 20 cal project so I will be giving them a try.

 

[Ledd Slinger]

The 3 grooves in the barrel are much wider than a groove in a barrel with more grooves. This in turn resists rifling wear from the lands on down the tube. Supposedly gives a person up to 20% more barrel life over a 6 groove style barrel. The general suggestion Ive heard is to twist the grooves a little tighter than normal when going to 3 groove because there are less edges to bite and stabilize the bullet. I have a X-Caliber SS 3 groove 11" twist on a 20 Tactical rifle, but have yet to shoot it and determine the barrel life advantage over the 6 groove 12" twist barrels I have used in the past.

 

[areaone]

I have three of Dan Mullers Barrels and they are excellent barrels. You will not be disappointed. Dan is a perfectionist in his barrell making.

 

[Milo 2.0]

I have three of Dan Mullers Barrels and they are excellent barrels. You will not be disappointed. Dan is a perfectionist in his barrell making.

^^^^+1
That said, I have a 6.5 3 groove Mullerworks barrel in 6.5x47, it's a slow barrel, but accurate as heck.

 

[potatoe]

From what I've read, Dan seems to be a great barrel maker. I haven't found one negative thing yet, it just seems like people like to stick with the top makers that they are used to - myselt included. I'm still on the fence not sure yet. Please keep the opinions coming.

Milo what kind of velocity are you getting? can you give details, load, barrel length etc? I'm wanting to do a 6.5L also.

 

[Rustystud]

All of Dan Muller's barrels, 3 groove, 4 groove, 5 groove, and 6 groove are exceptional.
He makes both cut and button barrels, all hand lapped to perfection. Dan's Barrels are in a class of their own. I have been using them for several years now.
Nat Lambeth

 

[flatlander]

I've had several PacNor 3-groove bbls over the past 15yrs - three on AR15 SR & MR uppers, and one on a M700 in 284. Two of the AR bbls were superior in every way - one won me our state SR championship a couple of times. The one on the match rifle upper was pretty mediocre, and went only 800rds before it started throwing fliers at 300yds. The one on my 1st 284 has been a hammer since day one, and still is, at 859rds. I've got four other Bartlein & Kriegers (4 & 5 gr) chambered in 284 & 280AI that are 30" long, while the PacNor 3-groove is 27"; yes, the 30s are faster with H4831 & N165 & various 180gr bullets, but not by much.

While I've used only Bartlein & Kriegers on my own rifles since 2006, I wouldn't shy away from using another PacNor 3-groove. 3,4, or 5-groove bbls have all been good for me - don't see much difference when it comes right down to it.

 

[JRS]

"The number of grooves has no real bearing on accuracy or barrel life".

Frank Green
Bartlein Barrels

 

[BoydAllen]

I believe that it is the quality of the final lapping that makes the most difference in the accuracy of top level barrels.

A friend who does some barreling slugs all barrels before chambering them, and as a normal part of evaluating barrels of customer's rifles. Among other things, this protects his reputation.

If someone were to pay for the installation of an expensive brake, or to have their action bedded, they would expect the final product to perform up to a standard, which if not met, in the absence of other information, might reflect poorly on quality of the smith's work.

 

[WayneShaw]

I agree with Boyd. Lapping can ruin a barrel if not done right. If you ever watched a .0001" indicator move while slowly rotating a barrel through the headstock, you would see. Remember, a bullet takes on the inside profile of the barrel, spinning at several thousand RPMs.

 

[sdean]

The bullet doesn't spin that many times in the barrel!

 

[JRS]

The bullet doesn't spin that many times in the barrel!

Really : MV x (twist rate) x 60= bullet RPM. In other words, the RPMs can be several hundred thousand RPMs, depending upon muzzle velocity.

 

[BoydAllen]

Most of the revolutions come after the bullet exits the barrel. If a barrel as 24" of rifling and has an 8" twist it makes three revolutions while in the barrel and thousands more as it traverses the distance to the typical target.

 

[JRS]

Assuming 3000 FPS, a bullet makes 12/8 or 1.5 revolutions for each 12" or 1 foot it travels in the bore. Accordingly, the RPM is 3000 x (12/8) x 60, or 280,000 RPM as it leaves the barrel. It's traveling quite fast while in the barrel.

Based on an 8 twist barrel Boyd.

 

[Ledd Slinger]

"The number of grooves has no real bearing on accuracy or barrel life".

Frank Green
Bartlein Barrels

Now let's post what Frank Green really said on the subject of 3 groove barrel life...

"Barrel life? Again I don't see a difference in the number of grooves effecting barrel life etc...One barrel maker who is making 3 groove barrels the last I heard was claiming they last longer. This might be true in a button rifled barrel because of the wider lands. On average I don't see a button rifled barrel lasting as long as a cut rifled barrel..."


So he even says it "might be true". Why do you think he used the word "might"? He doesn't make 3 groove barrels nor does he use them so he really doesn't know. Please do not chop up quotes to give deceitful information.

 

[BoydAllen]

JRS,
Yes I get that. If you notice I did not mention rate at all in my post. I was simply noting how many times the bullet revolves while it is traveling in the barrel for a given twist and length of rifling. I get the rate thing and how it is properly calculated. On the other hand publishing the calculations was a worthwhile exercise given that these posts get read by more people than actually post in a thread.
Boyd

 

[JRS]

"The number of grooves has no real bearing on accuracy or barrel life".

Frank Green
Bartlein Barrels

Pretty obvious who the new forum heckler is here... :

Now let's post what Frank Green really said on the subject of 3 groove barrel life...

"Barrel life? Again I don't see a difference in the number of grooves effecting barrel life etc...One barrel maker who is making 3 groove barrels the last I heard was claiming they last longer. This might be true in a button rifled barrel because of the wider lands. On average I don't see a button rifled barrel lasting as long as a cut rifled barrel..."


So he even says it "might be true". Why do you think he used the word "might"? He doesn't make 3 groove barrels nor does he use them so he really doesn't know. Neither do you Mr JRS. Take your chopped up quotes that boost your ego and go harass someone else...

There was no reason to quote the entire story. Frank happens to know just a bit about barrels Obviously, you know more than Frank about the manufacture of barrels : "on average". Comprendo? He is talking about button rifled barrels. NOT 3 groove barrels. The OP was questioning the 3 groove design. Period.