key hole with custom tube.

[4xforfun]

My brother has an old Rem 700 that he had re-barreled to a 22-250 30 degree improved 1-14 twist Hart BBL. This job was done 15-20 years ago by someone I will no longer let near my guns.

Anyway, he has fired 300 or so FF loads, some factory, some reloads...probably never on paper. he decided to start working with it, so I gave it a thorough cleaning. he started with varget and molyed 55 gr Ballistic tips. Pure disaster.....groups ranged from 2 -4 inches. NO custom anything should shoot that bad, so i did a little inspection of the crown with a magnifying glass and found no issue there. We switched out the scope figuring that that was the trouble. I told him to skip the Varget, so he loaded up some more 55 NBT along with some 55 gr v-max and RL-15. I cleaned the gun again.

This turned up a little better.....1 3/4 inch to 3 inch at 100 yards...still HORRABLE. Then I noticed that the bullets were going in the cardboard at an angle. ALL of them!!! I checked the 14 twist and 55 gr bullet on the JBM stabilization spreadsheet and it was over 2.5....beyond good enough.

Anyone have any ideas on what the problem could be? Could there be something I missed on the crown? These bullets should not be tumbeling. Two different powders, two different bullets and two different scopes, all tested on good shooting days on my bench equipment.

I AM STUMPED!!

Thanks,
Tod

 

[fredhorace77]

its too slow of twist. simple as that. try some 50gr. hopefully they will stabilize. over the years the bullets have gotten a more aerodynamic profile and need more twist to stabilize. bullet stability has more to do with the length of the bullet rather than the weight. if that doesn't work go to the 40's. if your dead set on running 55's your probably going to have to find the shortest 55 you can get. maybe a hollow point flatbase speer tnt

 

[LHSmith]

15-20 years and just starting to check it's accuracy now? Were moly bullets used previously for FF and the bore never cleaned prior to your cleaning? Moly attracts water. How smooth and uniform was the bore with a tight patch? Did you verify the twist was actually 1/ 14?

 

[Alex Wheeler]

Check the twist and slug the bore. A guy I shoot with at the club had a 6mm something or other, can't remember the cartridge, sent to him pre chambered. It would not shoot at all, thats when he discovered it was a .25 cal barrel.

 

[expiper]

4x4...bak in the day lots of the 22-250/220 swift etc were done with 15 twist bbls....check it out ....Roger

 

[CanusLatransSnpr]

I agree with everyone else, try some shorter bullets and see how she does! Speer's 52gr. Varmint hollow point is a damn good bullet. They're consistent in measurement and they're not awfully priced either!

Mike

 

[timeout]

Sure seems like a 1 in 14 22-250 should stabilize that bullet? I would have a competent gunsmith look at it before wasting a bunch of loading components. Something is HSID as they say.

 

[4xforfun]

I checked it....it is a 1-14 twist. The bore "felt" good as far as the patches go, which is all I have ever gone by since I on't have a borescope...yet. The tube never saw moly till he started load development just the other day. Tube was clean....TOD SOEBY CLEAN (for anyone who knows me...the definition of ANAL when it comes to cleaning) I have shot 55 nd 60 gr bullets (both moly and non moly) in my 14 twist swift for 20 years....the twist is not the issue. The JBM calculator figures in length, caliber, weight, speed, temp, baro, etc..... A stability factor if 1.4 is way good....he is TWO POINT FIVE with the 55 grain Ballistic tip.....................................................................

OK...I just rechecked the JBM....double checked all of the numbers, since 2.5 seemed whacked. The new numbers I get with the NBT is .734 at 10 degrees F. NOT ENOUGHT TWIST.


REALLY.... 55 Gr in a 14 twist not stable????

I just triple checked the numbers in JBM again...... .734....WOW...that would explain the keyholing!!! How _N-L I came up with over 2.5 is beyond me...garbage in garbage out!!!

Anyone have the length ofa 40 grain bullet?

 

[timeout]

Sure seems like a 1 in 14 22-250 should stabilize that bullet? I would have a competent gunsmith look at it before wasting a bunch of loading components. Something is HSID as they say.

OOPS!

 

[4xforfun]

I just checked the only bullet I have on hand less than 55 grains on JBM...52 grain berger flat based bullet..probably 20 years old. JBM gives me 1.017...... in the yellow.

 

[LHSmith]

I just checked tha only bullet I have on hand less than 55 grains...52 grain berger flat based bullet..probably 20 years old. JBM gives me 1.017...... in the yellow.

Yikes ! ...makes one wonder how Mike Ratigan won the FISS (Super Shoot) shooting a similar bullet at a similar velocity, at the same twist..... that according to JBM .....is poorly stabilized?

 

[CJ6]

Tod, A 55 gr NBT is .812, A Sierra 52 gr HPBT Match is .725. Hope this helps. Roger T

 

[4xforfun]

Tod, A 55 gr NBT is .812, A Sierra 52 gr HPBT Match is .725. Hope this helps. Roger T

The 52 grain Berger's are only .710 inches and come in at 1.01...ragged edge!! I am going to need 45 grain or less to make JBM happy!! I was just checking the Remington website...looking at the 22-250 and 220 swifts...all that I have seen are 1-14 twist!!! How many million 55 grin bullets do you think have been successfully shot out of those guns???

Funny story..My brother walked in a few min ago and the first thing out of my mouth was that I found his problem...He laughed at me and said that HE had found the problem. He went out to the 25 yard line and picked up his target (cardboard box) that he shot first on Saterday to make sure he was on target and set it on my counter....THE BULLET HOLES WERE COMPLEATLY SIDEWAYS!!!!!!

He is picking up some lighter V-MAX and NBT's right now.

 

[4xforfun]

how many of you out there have sucsessfully shot 55 grain bullets out of your 22-25-/220 swift/22whateveryoucallit?

I am kinda curious.

Thanks,
Tod

 

[CJ6]

Yeah, my 6-284's (12 TW) did that with 95 SSTs and a 1' - 4' spread. The 52gr Sierra's or 53gr AMaxs run pretty good for me.

 

[260Ravage]

I had a 14 twist 220 swift that loved 52 berger HP. It didn't like any 55 grainers. go figure.

 

[rocketron]

40 gn sierra measure .566

send a pm if you would like to try some. i have about 50

Ron

 

[CZ550]

Tod, I have a 14 twist 22-250ai that will stack 40gr Blitzkings. But 52 grain bullets dont shoot very well at all no matter what I try best I could get was occasional 1 MOA group. I have always assumed it was twist related and I bet you are seeing the same issue. FWIW the 40 gr blitzkings shoot very well.

 

[LHSmith]

I have had 2 mdl 700 Varmint Specials that were most accurate with 55 Nosler Ballistic tips. My son shot a 700 Varmint in BR score matches for a couple seasons with 55 V-max and did a respectable job for factory class. All three were 22/250 chamberings.

 

[4xforfun]

I have had 2 mdl 700 Varmint Specials that were most accurate with 55 Nosler Ballistic tips. My son shot a 700 Varmint in BR score matches for a couple seasons with 55 V-max and did a respectable job for factory class. All three were 22/250 chamberings.

And they were 1 -14 twist tubes. Again...Go figure.