17 Squirrel keyhole

[txdan]

I saw this once. He had a 6BR barrel with 20 BR ammo.

 

[hogpatrol]

Twist is 1-12 do you think this is my problem?

Good grief, why didn't you state that at the beginning? WAAAAY too slow. Even .17HMR barrels are 9 twist and they're shooting 15 to 20 grain bullets. You probably realize this by now but you are spinning your wheels. It ain't NEVER going to shoot 20s let alone 25s.

 

[farmer44]

So what would you suggest?

 

[farmer44]

Other than the obvious that I bought someone's mess do you feel any weight Bullet would work?

 

[hogpatrol]

So what would you suggest?

Pull that barrel and change to a 1-9 twist, NOT A 1 in 10! You'll be able to shoot anything up to 30 gr bullets. As far as what would work? Nothing, at least at the altitudes hunted in the U.S. Farmer, I wouldn't waste any more time on that barrel. If you have your heart set on the squirrel, its a simple albeit costly fix, a new barrel.

 

[farmer44]

So is there any thing I can do with this barrel? Perhaps another chambering?

 

[hogpatrol]

So is there any thing I can do with this barrel? Perhaps another chambering?

Regardless of chambering, with anything readily available in bullets, 20s to 30s, it will still keyhole.

 

[JohnHenry]

I don't believe that you will be able to stabilize even a short 20 grain bullet. Looking at the JBM Ballistics website and calculating the Miller Stability Factor, the shortest 20 grain bullet in their data base is unstable at 3500 fps. The shortest bullets in their data base are the Berger 20 gr. match varmint and the Nosler Varmageddon 20 gr. FBHP, both having a length of approx .50". The stability factor at 3500 fps is .95 with factors of 1.3 or greater considered stable.

PS: A little hard to believe anyone makes a 12 twist 17 caliber barrel, but I see Pacnor's website indicates they do.

FYI, If you could find a custom 15 gr. bullet 0.4 inches long, it would have a stability factor of 1.31 at 3500 fps. Genco advertises a 16 gr. FBHP.
http://www.saubier.com/genco/index.html

 

[farmer44]

So can I rechamber this to another 17 caliber that will except the 1-12 twist barrel?

 

[JohnHenry]

So can I rechamber this to another 17 caliber that will except the 1-12 twist barrel?

Even if you went to a larger head size cartridge like the 17 Remington, a 0.5" long 20 gr. bullet at 4500 fps would be unstable having a stability factor of 1.0 in a 12 twist barrel. I would check on the length of the 16 gr. Genco bullet mentioned in my prior post.

 

[swd]

Sorry to tell you, but it's a tomato stake. Did you have it barreled or buy it that way?

 

[farmer44]

I am thinking of perhaps changing the cartridge to one that will work with a 1-12 twist any suggestions.

 

[JohnHenry]

Checked some older(2006 & 2009) Berger spec sheets that I have. Was surprised to see that the recommended twist rate for the now discontinued Berger 20 gr. FBHP was 1 in 12" or faster. May want to try the 20 gr. FBHP Nosler Varmageddon which is the same length(0.50") as the 20 gr. Berger FBHP. Actual range performance trumps any stability calculation. The Miller Stability Factor calculations may prove to be conservative. Wish you success.

https://www.midwayusa.com/product/1...-172-diameter-20-grain-hollow-point-flat-base

PS: Saw a note on the Berger site indicating that the Miller Stability calculation is most accurate for boat tail bullets. The calculation underestimates the stability for flat base bullets.
Also, saw Ron Reed's post on the Saubier site that they are planning to make some short light 17 caliber bullets in 2017.

 

[rickiesrevenge]

Speed is a factor for stability but it doesn't have nearly as big of effect as barrel twist. Berger used to make a 15gr and 18gr bullet. I don't have any to measure but this site says that their .466" long. http://www.shootforum.com/forum/bulletdb.html . Using bergers twist calculator you won't be stable with these either. Barely stable at 6000fps. http://www.bergerbullets.com/twist-rate-calculator/. So going to a bigger cartridge isn't gonna help, at least from running the numbers. I read a long time ago about Dick Saunders making a trimmer to trim bullets down to shorter lengths. This is probably about your only option. The only other thing I'd try is calling the small bullet makers to see if they'll make you some. BlackHole bullets has made me some special bullets in the past and its worth the call.

Aaron

 

[farmer44]

I have decided to just re barrel the gun and move on. I would like to say THANKS to everyone for all the input and wish all a very merry Christmas.

 

[Tommie]

Twist is 1-12 do you think this is my problem?

Holy plumbing, Batman! There's a vital piece of information.
Sir, your barrel is essentially useless.

 

[JLT]

I have decided to just re barrel the gun and move on. I would like to say THANKS to everyone for all the input and wish all a very merry Christmas.

Good decision! More than likely you will spend less money by swapping out the barrel for one that will suit your needs. It has been said . . . No matter how hard you rub, you can't shine a turd.

 

[Tommie]

Has me wondering why a barrel manufacturer would even produce such a useless barrel. All I can picture is somebody with way too much time and money trying to see if they could break a velocity record by shooting 15 grain bullets in a necked-down 308 Winchester case.

I see that you're posting on Saubier as well. The advice regarding the 20 grain XTP is probably correct but I REALLY would not continue trying to make that barrel work. Chalk it up to a learning experience and get a 1-9" barrel.

My father was a master organic gardener. He learned very early that some plants, for whatever reason, were doomed to be weak and sickly no matter how much TLC they receive. Instead of spending all kinds of time trying to keep a cull plant going he'd yank the thing out of the ground and concentrate on the productive plants. Pouring all kinds of time, money and energy into that 1-12" barrel is basically the same thing.

Let us know how the rebarrel process turns out.

 

[farmer44]

I will keep you posted

 

[Shaggy357]

1-12" with 20gr bullet just has to be loaded hotter than h3!!. Not good for brass life, but that little sucker should be able to accomplish the feat. Quickload help? Anyone? Anyone? Beuhler?