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Bill Wynne
12-13-2008, 07:00 PM
Has anyone had success with a short barrel on a .22 bench rifle? I am thinking of between 19 and 22 inches. It seems like a short stiff barrel would work well but I have not seen one.

Concho Bill

cadman1275
12-13-2008, 07:30 PM
I had a short Lilja barrel on my Annie 2013. It would do good in "NO" wind conditions, but the minute someone decided to breath in my direction I had no idea where the bullet would go. That barrel was 21" in length. I now have a 26" barrel and it rocks in either condition.

Bill

Dennis Sorensen
12-13-2008, 08:39 PM
With the target ammunition you are using is the velocity greater or less in a 26 inch barrel over a 21 inch barrel? Somehow I thought maximum velocity was reached in fairly short barrels in .22 LR and slowed down in longer barrels but I have never tested that theory...

John Kielly
12-13-2008, 09:33 PM
When I shot, it was anecdotal around prone smallbore circles that shorter barrels achieve more velocity but longer barrels even out velocity variations. I never got around to testing that because, as well, in the warmer temperatures here, some of the more spirited target loadings (notably early manufacture Federal) would go supersonic in shorter tubes, which is why you don't see a lot of those bloop tube Annies hereabouts.

Rich In Kansas
12-13-2008, 09:43 PM
higher velocity drifts more in the wind with the .22 just under the speed of sound. The opposite of centerfire that is much above the speed of sound.

Beau
12-13-2008, 10:33 PM
The gun I currently shoot had a 21 inch barrel on it a few years ago. It was as accurate as anything out there when there was relative calm or light wind. In the wind, the longer barrels would win. I assumed, and I believe correctly, that the increase in velocity made the gun harder to shoot in the wind. I had it rebarreled with a 24 inch barrel and it made a huge difference. The gun shot better in the wind with the longer barrel. I still had another one with a 21 inch barrel and I tested them side by side. The 21 inch barreled gun was more accurate in the calm but the longer barrel would outdo it pretty bad in the wind. Ultimately, I settled on the longer barrel. I believe there is an advantage up to about 24 inches. After that, I think you start to fall off because with the slow ammo we use, I think you start to lose stability. I know that's not always the case, but it's been my experience.

crb
12-14-2008, 05:20 AM
Here is a rifle with an Anschutz "match" bbl from Numrich. Under 20", 1.25 blank dia that I left as. Smooth as a baby's butt on the inside when viewed with a borescope. The 3rd bull is a .165 and the 4th bull is a .212. I would like to see someone that really knows what they are doing fit one of these blanks to a good match gun.

http://i114.photobucket.com/albums/n260/raayjayy/Rem40xlhfullinprogress.jpg

nickloy
12-14-2008, 07:31 AM
Rich,
When did rimfire shooters rewrite the rules of physics?
A bullet of a given weight will always drift less at higher vel than at lower vel.The statement the a bullet drifts less at low vel is nothing more than an old wives tale,if you doubt this just look at the drift tables or research the formulas for drift and stick in your own vel and weight data and see what the results are.
Nick Loy

Rich In Kansas
12-14-2008, 08:00 AM
I would think all top quality match ammo would be of the high velocity type if higher velocity was better. But here is a write-up from the NRA Book of Facts that explains it as well as any and better than me, enjoy:

Those unfamiliar with smallbore rifle competition are often surprised to learn that target shooters almost universally use standard velocity ammunition in preference to the many varieties of high and hyper-velocity rounds available. The reason given is the low-velocity ammunitions resistance to wind deflection.

Despite what might seem at first to be the case, wind deflection is not proportional to the time of flight. Instead, it is proportional to the amount of delay in the flight caused by air resistance. The 1145 f.p.s. standard velocity .22 long rifle round takes .287 seconds to go 100 yds., but would take only .262 seconds to cover the same distance in a vacuum. The latter figure is easily found by dividing 300 ft. by the speed of the bullet (1145 f.p.s.), which would remain the same throughout its flight if it were in a vacuum. Thus the delay caused by air resistance is .025 second with the standard velocity ammunition.

The 1335 f.p.s. high velocity ammunition, which will take .259 second to cover 100 yds., would take only .225 second in a vacuum. Thus, the delay for this bullet is .035 second or 37% greater than that of the standard velocity round .22.

The high speed round, then, suffers about 37% more wind deflection than the standard velocity.

This remarkable result is due to the very rapid rate at which air resistance increases with increase in bullet speed in the region near the speed of sound. The .22 rimfires rimfires are the only important rifle cartridges that occupy this speed range, and they are the only ones that show more wind deflection as velocity is increased.

While air resistance always increases when the bullet is shot faster, the rate of this increase is less steep at supersonic velocities. Rifle bullets in general, contrary to the case of rimfires, are made less sensitive to the wind by raising their velocities.
NRA Firearms Fact Book

Rich In Kansas
12-14-2008, 08:19 AM
I think the velocities are a bit high in the NRA fact book. So I went to JBM online and calculated for 1080 and 1150. The 1080 shows 1.3 inches of drift in a 10 mph cross wind and the 1150 shows 1.5 inches. But who ever saw the wind the same constant velocity from bench to target:)

Mad`
12-14-2008, 09:28 AM
I've competed and done pretty well in rimfire and centerfire benchrest. I have found that a .22 lr @ 50 yards will drift a helluva lot more than a 6PPC @ 100 yards in the same velocity wind.
I don't know why this happens, but it is just my experience.

Vibe
12-14-2008, 09:58 AM
Rich,
When did rimfire shooters rewrite the rules of physics?
A bullet of a given weight will always drift less at higher vel than at lower vel.The statement the a bullet drifts less at low vel is nothing more than an old wives tale,if you doubt this just look at the drift tables or research the formulas for drift and stick in your own vel and weight data and see what the results are.
Nick Loy
That's just a bit over simplistic. First, the bullet that loses the most velocity will drift more, and centerfire ammo generally have better low drag shapes.
2nd - it's not so much the actual velocity so much as it is staying out of the trans sonic turbulence. Even centerfire shooters try and stay above that range all the way to the target. Since rimfires cannot do that, we try and stay out of it by remaining slower.

Bill Wynne
12-14-2008, 10:10 AM
Please try to stay on subject.

I believe that we are once again off on a tangent or to put it another way, chasing rabbits.:)

Forget about the wind effect on different types of bullets, I am asking if anyone has had success with a short barrel 22 bench gun.

Concho Bill

Rich In Kansas
12-14-2008, 10:40 AM
I was trying to tell you why you don't want a short barrel as well as others. I don't think that is off topic. I have only seen a couple of short barrels that have done well in 14 years of shooting rimfire benchrest (br50 and ara). They were all on xp-100's converted to rimfire. And many of those times they did well were in low wind or night shoots. I've never seen one do well in 15 mph plus winds but I'm sure someone can recall a case.
Also a short stiff barrel will not respond well to a tuner.
And finally, as Vibe mentioned, another effect not related to wind drift, is if a rimfire bullet reached the speed of sound it hits turbulence as it drops through the speed of sound that causes a loss of accuracy. So you want to avoid getting to the speed of sound which a short barrel might achieve with some standard velocity ammo. I've had it happen with one lot of Eley 10x years ago but only on the first shot from a 25 inch barrel. That lot probably would have kept all its shots above the speed of sound in a short barrel.
And finally again, there is a reason short barrels are rarely seen at ARA matches where weight is not a factor.

Bill Wynne
12-14-2008, 10:53 AM
With the target ammunition you are using is the velocity greater or less in a 26 inch barrel over a 21 inch barrel? Somehow I thought maximum velocity was reached in fairly short barrels in .22 LR and slowed down in longer barrels but I have never tested that theory...

I believe that this may be the best question. It would be interesting if someone would take a long take off barrel and with some ammo, known to be consistent, cut off an inch at a time and test at each cut.

It might take slower ammo to work well with a short barrel. When all of this is done, it may just be that a 26 or 28 inch length may just be the best length. It may just be that we are just a bunch of copy cats.:)

Concho Bill

Dave S
12-14-2008, 10:54 AM
quote: "I've never seen one do well in 15 mph plus winds but I'm sure someone can recall a case." quote

I've never seen anyone do well in a 15 mph wind either, short barrel or long..

Dave

Steve Keim
12-14-2008, 04:25 PM
Bill,
Do you really want to be known here in San Angelo as "ol' short barrel?":)
Steve

Bill Wynne
12-14-2008, 04:31 PM
Bill,
Do you really want to be known here in San Angelo as "ol' short barrel?":)
Steve

Good grief!

Well, Steve, without friends like you, where would I be.

I think I will keep the barrel I have.

Concho Bill

steve b.
12-15-2008, 10:09 AM
"I believe that this may be the best question. It would be interesting if someone would take a long take off barrel and with some ammo, known to be consistent, cut off an inch at a time and test at each cut."

You are changing alot more than just barrel length when you do something like this.

In simple terms, you are chaning the barrels natural harmonic tune, and more so, if there was a nice choke lapped into the barrel, you are removing it. Your barrel ID at the time of bullet departure is actually growing in dimension.

Further, you are taking a rifle apart and putting it back together, as well as recrowing it each time.

Many variables in that process to completely remove / manage. Not practical for most shooters / smiths.

s.

Bill Wynne
12-15-2008, 10:58 AM
"I believe that this may be the best question. It would be interesting if someone would take a long take off barrel and with some ammo, known to be consistent, cut off an inch at a time and test at each cut."

You are changing alot more than just barrel length when you do something like this.

In simple terms, you are chaning the barrels natural harmonic tune, and more so, if there was a nice choke lapped into the barrel, you are removing it. Your barrel ID at the time of bullet departure is actually growing in dimension.

Further, you are taking a rifle apart and putting it back together, as well as recrowing it each time.

Many variables in that process to completely remove / manage. Not practical for most shooters / smiths.

s.

Steve, I understand that a perfect test requires constants and we would be cutting the choke and changing the crown.

What I am proposing to test for velocity change only. I agree with you, there would be just too many variables to test for accuracy.

What would be wrong with this? A person with a throw away barrel could shoot a few rounds through a chronograph and record the results then cut an inch off of the barrel with even a hack saw or a band saw and crown the muzzle by hand. The process could be repeated until the barrel is too short for safety. This process could be completed in a couple of hours when the atmospheric conditions are fairly constant and you would be testing the same barrel.

Concho Bill

steve b.
12-15-2008, 11:31 AM
Ok.

I found this on .17 HMR barrels relating velocity to length. You may find this interesting.

http://www.bullberry.com/HMRdata.html

Fred J
12-15-2008, 01:45 PM
Just how many old barrels do you have? I have found the the highest velocity was not necessarily the best accuracy. Slect the barrel for it's properties and then select the ammo that shoots best. This is an old subject, that has never been answered to the point the question never gets asked again. Longer barrels have proven to be more stable for me, and that's why I use them.

Guy Pike
12-15-2008, 04:24 PM
Know little on the subject I ask this. Does the extra rotation achieved by the longer barrel have any effect on bullet stability?

Fred J
12-15-2008, 04:58 PM
Guy:
There is no extra rotation with the extra length. 1 in 16 is the same at any length.

Guy Pike
12-15-2008, 05:31 PM
Fred: With a 1 in 16 twist the bullet would rotate once in a sixteen inch barrel. eh? In a 24 inch barrel it would rotate 1 1/2 times would it not?

Joe Friedrich
12-15-2008, 05:43 PM
Has anyone had success with a short barrel on a .22 bench rifle? I am thinking of between 19 and 22 inches. It seems like a short stiff barrel would work well but I have not seen one.

Concho Bill

Bill, have a 21" BM .900 straight barrel on a Hall, that is in a Robertson stock. The last time it was taken out I shot Dan's PSL targets and some RBA targets with good solid results. There hasn't been a lot of testing with it, but what has been tested so far, surprises even myself.

Joe

Fred J
12-15-2008, 09:06 PM
The bullet will still only be rotating on a 1-16 rate.

Dennis Sorensen
12-15-2008, 10:59 PM
Fred: With a 1 in 16 twist the bullet would rotate once in a sixteen inch barrel. eh? In a 24 inch barrel it would rotate 1 1/2 times would it not?

The barrel length does not affect the rate of twist, it is constant... but a velocity change will change the rpm of the bullet.

Bill Wynne
12-16-2008, 05:15 AM
Bill, have a 21" BM .900 straight barrel on a Hall, that is in a Robertson stock. The last time it was taken out I shot Dan's PSL targets and some RBA targets with good solid results. There hasn't been a lot of testing with it, but what has been tested so far, surprises even myself.

Joe

Very interesting, Joe. That is about the length I was considering.

It would seem to me that there are some sound reasons why this type of rifle would be a real shooter.

As far as I know this is just theory and it may be a very wacky one at that.

Let us assume that a short steel rod (barrel in this case) will bend less than a long steel rod of the same diameter. I don't know these figures to be true, but a 27" barrel may flex, due to vibration upon being shot, twice as much or more than a 20" barrel and that is the basis to the short stiff theory. Another factor might be that the bore would be straighter in the shorter barrel.

All kinds of factors may also enter and become problems. There may be that a greater muzzle blast that could cause the bullet to be less stable. It may require a slower bullet or a pistol round to work best. I just don't know.

Concho Bill

garrisone
12-16-2008, 07:13 AM
Very interesting, Joe. That is about the length I was considering.

It would seem to me that there are some sound reasons why this type of rifle would be a real shooter.

As far as I know this is just theory and it may be a very wacky one at that.

Let us assume that a short steel rod (barrel in this case) will bend less than a long steel rod of the same diameter. I don't know these figures to be true, but a 27" barrel may flex, due to vibration upon being shot, twice as much or more than a 20" barrel and that is the basis to the short stiff theory. Another factor might be that the bore would be straighter in the shorter barrel.

All kinds of factors may also enter and become problems. There may be that a greater muzzle blast that could cause the bullet to be less stable. It may require a slower bullet or a pistol round to work best. I just don't know.

Concho Bill I have a 1813 model -54 action Anschutz rifle with a 21 inch bull barrel -stainless steel barrel and have done very well this year shooting at the gunclub I belong to. I have won five out of twelve matches with it and shoot inside a chicken coop. garrisone.

Rod Collins
12-16-2008, 07:26 AM
I read an article in Precision Shooting a few years back, Where they cut off 1" at a time. You should find it ,and read it, before you do it all over again.

garrisone
12-16-2008, 08:22 AM
Rod: I will keep the rifle as it is for where I am shooting. It has done very well for me. If you could tell me where I could find the artical you mention I would like to read it. When I bought ammo from your brother he too remarked about the artical and said that generaly these rifles would not shoot. I am shooting the rifle inside a chicken coop and it is doing very well for me. Thanks for your reply. garrisone.

Boer bok
12-16-2008, 08:48 PM
Bill i am going to bring hack saw over in the morning
get ammo ready$rest we will start cutting one inch at a time
off and see where it shoots best.
Jack

Boer bok
12-16-2008, 08:52 PM
Bill i am going to bring my hack saw over in the morning
get ammo & rest ready. We will get down to the neety-greety
and find out one way or the other.
Jack

Mad`
12-17-2008, 02:47 PM
How you gonna crown it after the hacksaw job?

Bobby T.
12-17-2008, 03:12 PM
While you are having fun you might as well bring a dremel along and plenty of bits to touch up that crown.

Later,
Bobby

Paul H
12-17-2008, 03:18 PM
Assuming a taper lapped barrel, it would be more interesting to cut the barrel off from the breach and cut a new chamber each time you bob off an inch. Yep, alot more machine work, but perhaps a more accurate assessment. And while you're at it, might as well index the barrel ;) It would be interesting to see if there were changes in the indexing as the barrel was shortened.

RegisG
12-17-2008, 03:20 PM
Some wind computations using AL_BAL 22EXTBAL program

Deflection @ 50yds with 10mph windis :
1047fps 1.66 moa
1072.....1.82
1022.....1.62

Above the 1072 the change is much faster.

I don't know if there is enough difference in typical barrel lengths to make 25fps change to get 0.1 +- MOA difference

Thank you,
Regis

Boer bok
12-17-2008, 04:37 PM
Bill I will bring my hacksaw over and we can solve the question.

BOER

Bill Wynne
12-18-2008, 02:56 PM
Assuming a taper lapped barrel, it would be more interesting to cut the barrel off from the breach and cut a new chamber each time you bob off an inch. Yep, alot more machine work, but perhaps a more accurate assessment. And while you're at it, might as well index the barrel ;) It would be interesting to see if there were changes in the indexing as the barrel was shortened.

This test is better suited to a barrel manufacturer or a respected gun writer and experimenter than a guy like me who simply has a chronograph and a willing friend with a hack saw.

Other than getting the burrs out of the muzzle I don't see what harm would come from sawing off the end of the barrel and shooting a few rounds through it to determine velocity only. Accuracy is not a factor for this test. We will work on that latter.

I think that this post by Steve has a lot of bearing on this problem but is is done with a .17 HMR and not a .22 Long Rifle with target ammo.


Ok.

I found this on .17 HMR barrels relating velocity to length. You may find this interesting.

http://www.bullberry.com/HMRdata.html

Concho Bill

Paul H
12-18-2008, 03:19 PM
I thought the question was the ability of the shorter rifle to shoot accurately, not what the velocity is for various barrel lengths. And hence the suggestion to go to a thorough, albeit time consuming and expensive test to find out what happens at various barrel lengths.

If I ever get serious about rimfire benchrest I'd be curious to try some other options such as the gain twist barrels being discussed by the centerfire folks. I'd be curious to see what happens if you have a barrel that starts at say 1-20 and transitions to 1-17 at the muzzle performs.

Mad`
12-18-2008, 04:37 PM
About four years ago I happened to be at our benchreest range one day and two of the better and respected centerfire BR shooters were there as well. One of them is a centerfire BR gunsmith. They were reloading and testing their 6PPC's. One of the barrels on a Panda was old and worn out. The groups were opening up so they decided to do an experiment. They hacksawed the end of the barrel off at an eyeballed 45 degree angle, debured the crown with a hand turned drill bit that was larger than the I. D. of the barrel, and ran a patch down the tube.
Then they shot some groups. The groups were just as tight (about .250") as the barrel was before the hack job, but the groups moved about three inches in the direction of the hack job. Then they cut another 45 degree angle in the opposite direction. Again, more .250" groups but three inches in the direction of the hack job. By then they were tired of sawing and unscrewed the barrel and screwed a new one on and kept up with their load development.

Conclusion: The condition of the crown and the barrel being about an inch shorter after every cut, had no effect on accuracy.
We were all scratching our heads. :confused: They asked me if I wanted to try it on my 40X rimfire BR gun:eek: but I declined.
Dale McClure

Guy Pike
12-18-2008, 06:47 PM
So if the longer barrels shoot better in very light wind conditions due to slowing the bullets velocity, why not develop slower ammo for short barrels to shoot in the wind? Other than no demand to justify cost?