For what seems like forever I have always heard that a longer barrel gives more velocity and accuracy. (I know that is the case on muzzleloaders I have owned/shot).

I recently have been experimenting with a few rifle barrels on my TC ProHunter and really have not been impressed with the accuracy (1 1/2 inches on a good day and more like 2 1/2 -3 inches at 100yds for the most part). After reading up on it I know the TCProHunter is NOT built primarily for accuracy....it's more of a "system" and I like the idea of shooting the same frame plus it fits my body well....so nice to shoot but subpar accuracy at least for me (so maybe this is all me but with my Rem 700's I can shoot 1 - 1 1/2" groups consistently).

That said I did a little research and found the article in the link below. Mike Bellm is "THE" TC expert so if it is information on his website it's probably accurate. Bottom like s that they cut the 28" barrels down to 23" and re-crowned them and significantly tightened the groups with minimal velocity loss. Apparently the longer barrels (at least on the TC barrels) have harmonics, etc that effect accuracy.

http://www.bellmtcs.com/store/index.php?cid=580


I saw wondering what the experts on this forum think about longer barrels vs standard barrels on bolt action rifles. As I said, just curious.

A longer barrel makes more velocity, but not more accuracy. In fact, in some barrels the shorter the barrel the more consistenly it shoots.

The slower the powder burn rate the more it will yeild more speed per inch of barrel.

So a side question, what do you think of the new Superperformance Hornady ammo vs their standard ammo. Do you think they gave up accuracy for velocity?

Each rifle will like some ammo and not others, so it depends.

The only two boxes of Superperformance I ever tried, in a 30-06 and a 308, were not as accurate as other choices, but that is just two rifles, so a small sample size and it really does depend on what the rifle likes.

As far as barrel length, longer than 24" begins to feel unwiedly to me, and 22" is even better.

I have found the 223 Superformance to be very accurate in the 4 rifles I fired it in so as mentioned ....it depends.

I also found as you have the the T/C and other break open rifles can be accurate but more often are Not

My encore would hold sub inch groups in .308. If you're wanting to keep your rifle, it may be worth it to have the barrel cut down.

I don't buy centerfire ammo. I have not had any clients that have come out with that ammo, so I have no first hand experience with it. But reading what Jeff reported suggests Hornady is making some hot loaded ammo, and not every rifle will like that. It is no different than what we do in search of "the" powder charge. Quite often there is a low speed node and an upper speed node where the rifle/ load will shoot. And quite often that is not at maximum powder charge. So when increasing powder charge the rifle gradually tightens up then once you get to a certain point exceeding that good shooting load the groups open up. That shows that you found then exceeded the node.

The "node" as it is called is working with barrel harmonics instead of against them. When a bullet travels down a barrel the barrel whips in a sine wave. In some cases an observer can see the wave as the rifle is fired. The node happens when the barrel was in upward deflection - bullet leaves the muzzle - barrel begins downward deflection. So the bullet left the muzzle when the barrel had paused motion. If the load is below or above optimum powder charge the barrel is still moving when the bullet leaves the muzzle creating no consistency.

The shorter the barrel the less pronounced the sine wave is, so the wider the optimum powder charge range is. In layman's terms the short barrel is less picky about what the powder charges are you feed it.

Among my own rifles the evidence of this is seen in my 7mm Rem Mag with a 26" Light Palma contour versus my 7mm-08 with a 20" M-24 contour. The 7mm Rem Mag has a narrow powder charge where it shoots best. The 7mm-08 shoots well on several charges, but showed clearly where the charge needs to be if you know what to look for.

I am dubious about barrel length being the accuracy-killer there. All barrels flex, this is why we fool around with different handloads until a bullet/powder combination consistently gets the bullet to leave the barrel in-between flexes.

A shorter barrel of the same diameter will flex less - but it still flexes, and you still will not get top accuracy until you get the bullet to leave the barrel in-between flexes.

Those rubber do-dads that slip over the barrel and allow you to alter the harmonics of the barrel work best on longer barrels. - I'd try one of those, following the directions carefully. It does the same thing as trying different handloads, but by changing the barrel harmonics instead of by changing the load.

If somebody talks about significantly shortening a barrel with "minimum velocity loss", they are full of gun grease. - There ain't no such thing as a free lunch. Shorten the barrel, and you are going to lose velocity.

I shortened the barrel on my 1885 Winchester, but gee, it started off at 28 inches. I shortened it to 24 inches for better handling qualities, it was really awkward to wave around. - Heavy, too.

It's your gun, do what suits you - but I'd be careful about following the 'wisdom' of somebody who talks about significantly shortening the barrel without significant velocity loss. If you do one, you're going to get the other too.

Physics... - It's the Law!

I've heard people say for years that in .257wby you had to have a 26" barrel.

I had a 26" barrel .257wby and chronographed it at 26" with 2 separate loads then had the barrel cut to 24" and retested it.

average loss was 50fps.....on a bullet leaving the muzzle at 3500+fps it really didn't matter.

It certainly varies among individual guns. My .375 Holland began life with a 24" barrel. I shot it awhile but finally convinced myself to shorten it a bit for close-quarter handiness. So I lopped the barrel back to 22". I was happy that my favorite load with the 300 gr Nosler lost just 65 fps after losing two inches of barrel. I kinda wish I'd shortened it to 20", but I left it at 22.

The moral? Choose a barrel length that's ergonomically right for you....how it balances, how it handles. And don't worry all that much over velocity loss. Lots of riflemen these days are cutting a foot off their barrels and putting on a suppressor. Early reports are that deer and hogs can't tell the difference!

Ive gone through all this guess work through the years and minused it out with bull barrel guns. Sporter weight guns more often than not will be a little different every time I take them out to shoot them, but the bull barrel guns are always on the money. I have 20 in bull barrel guns for hiking and 26 in for those overlooking valley short hikes. I bought a Winchester varmit .308 bolt gun one time and bought some cheap monarch .308 150 grain soft points. I put a cheap 6x18x50 banner on it and adjusted the 1/4 screws on the trigger and it gave me three shot groups in a metal sign at 100 yards that I couldn't even see, because they were always in the same exact hole. I cant find a sporter weight that will do that. When I miss an animal with my bull barrel .223s or .308s its my fault and I don't even second guess the gun.

HERE IS THE TEXT FROM THE ARTICLE I WAS REFERING TO..... AS I MENTIONED, THEY WERE SPECIFICALLY DISCUSSING TCPROHUNTER BARRELS


A couple weeks ago, I performed a single test of 5 different T/C Pro Hunter rifles that literally cut their group size in half. Before I tell you what I did, here is a list of the guns/calibers used in this seemingly simple test...

All guns had the 28" fluted Pro Hunter barrel...

All guns had Mike Bellms oversize hinge pin, heavy duty locking bolt spring and 51 lb. hammer spring...

All guns had trigger jobs with the triggers being set from 2 1/2 to 3 lbs...

All guns were shooting factory ammo...

All guns were checked before testing to make sure all mounts were tight...

Here is a list of each caliber used in the test, along with the ammo and group size before/after. I will also point out that there were 2 3-shot groups fired from the bench at 100 yards before the test and 2 3-shot groups fired after the test with the average group size listed for a ruler reading of group size measured center to center...

1) 22-250 / 55 gr. Federal Premium, before - 1 3/4" / AFTER - 3/4"...

2) 25/06 / 117 gr. Hornady Spire Point, before - 2" / AFTER - 1"...

3) 7mm Rem. Mag. / 140 gr. Nosler Partition, before - 2 1/2" / AFTER - 7/8"...

4) 308 / 150 gr. Remington Core-Lokt, before - 1 1/2" / AFTER - 3/4"...

5) 300 Win. Mag. / 180 gr. Ballistic Silver Tip, before - 2" / AFTER - 1"...




Okay, what was the ONLY thing done to these guns to cut their group size in half?

I cut 5" off the barrel and recrowned the muzzle!
Well, that may actually be two things but, it stands to reason that if you cut a barrel back, it automatically gets recrowned...


So why did these guns start shooting more like what they were supposed to with a 23" barrel instead of a 28" barrel?

Excessive "whip" and "vibration" as well as a total change in "harmonics"...

Here is a simple test that you can do and one that I have shown many customers. Remove your barrel from the frame and put the barrel lug in a vice and lock it down good and tight. Put a lead pencil in the muzzle end of the barrel. The wood is soft and will NOT damage the rifling or crown. Make sure the fit is good and tight. Now take a piece of paper and anchor it in front of the barrel and to where it comes in contact with the pencil. Now, with just your thumb and index finger, see just how much you can "flex" the barrel. You can very easily move the barrel 1/2" in all directions and depending on the pressure applied, it is easy to make a circle over 1" in diameter just from the barrel having so much give to it...

I have put these barrels in a lathe and run the lathe at 1,000 rpm and have shown customers how easy these barrels flex and bend with just finger tip pressure. What do you think these same overly long barrels do when a round is fired down the bore? They flex pretty much the same way but, too fast for the eye to see it. A shorter barrel though, will still flex but, to a lesser degree...

These Encore barrels also have what is referred to as a "step taper" and this too is a big cause of barrel flex. This is why that, when I build a barrel by barrel stubbing, I only use barrels that have a "straight taper" as this is what can be referred to as a self supporting structure. It does NOT whip around or flex like what the step tapered barrels do and with the vibrations lessened and harmonics dampened, accuracy potential of the barrel goes way up...

Will cutting 5" off of every barrel automatically make your barrel a better shooter? I cannot say 100% that it will but, I have yet to see one that it did not help at least to a certain degree and some more than others...

Let me also point out that something else that was noticed was "loose" spots in the bore. With all 5 of the rifles tested, when running a jag with a tight fitting patch down the bore, there was at least one if not two loose spots in the bore, with the first one usually at the 23 to 24" mark and then the second one at around 27". I cannot say for sure but, I believe this is why these barrels shot much better because of the elimination of these loose spots. This is something that you cannot "fix" in these long barrels and the only way to deal with it is to live with it being like it is or cut it off, recrown and go from there...

Velocity loss from going from a 28" barrel down to 23"? I did get to shoot the 25-06 and 308 over the chronograph and total velocity loss for both was less than 60 fps.. I was expecting more but, and this is only my opinion, I feel the oversize bore closer to the muzzle end of the barrel was the culprit. If the bore was uniform from end to end or the muzzle end of the bore had a slight constriction to it, I would have expected a greater velocity loss. The 25-06 really surprised me as this cartridge performs admirably in a long barrel and shows it's true velocity potential. Not so in the last couple of Encore barrels I tested...

It's things like this that show the p-poor quality and design standards of T/C. It's no wonder Mike Bellm and I have so much gray hair....

DAVID WHITE

Ive never owned a TC. I guess I like that quick back up shot. Ive herd of people having the same issues with various single shot brands and ammo brands used in them. I always figured it was a lot to do with the way the round was seated in the chamber. Maybe a little more wiggle room than the bolt guns.

I like my barrels short and haven't come across any accuracy issues. All of my hunting rifles have barrels that are 20" or less. My TC is 16.25" and sub MOA.