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Discussion Starter · #1 ·
Posts: 715
(10/5/01 11:57:08 pm)
Reply | Edit | Del All Let Me Share With You!!
A startling revelation came to pass today -

For the past couple of years, I've been shooting .264 diameter bullets down a .257 diameter barrel!

And the rest of the story - !

A pristine Husquarvarna made Swede Model 38, mfg in 1941, was residing in my gun safe, along with a couple others of the 1902 - 1906 vintage Carl Gustaf model 96's and a coverted '96/38.

In a wild moment of having too much time on my hands, I got to thinking of the 7x57 Ack Imp that nestled in the safe also (a rechambered and customized Brazilian Model 1908 Mauser) and how well it performed. Mayhap the Swede could be rebarreled and chambered in 6.5x.257 Ack Imp? The cases were somewhat compatible, the bases were close enough in diameter to fit the bolt face with a small amount of relieving and OAL cartridge length would be the same. Considering how well the 7x57 performed, the same case necked down to 6.5 should really be a whiz-bang!

Rifle clutched in hand and a "few" hundred in cash stashed in the pocket, I approached my erstwhile local gunsmith (of national repute) with the supposition. He agreed, especially as a few bucks were involved. He makes his own barrels from solid bar blanks, and pulled one from the overhead cabinet with the 1.25 machined diameter and bored. There was a 6.5 x 10 on the end butt, attesting to caliber and rate of twist. This was machined into a receiver matching diameter, a 26 1/2" bbl length, and a .650 dia muzzle. A target 11 degree crown was machined, the barrel fluted with 8 equal land/groove width flutes, tight chambered for a custom provided 6.5x.257 Robt's AI dummy loaded cartridge, the received drilled and tapped for a Redfield Jr scope base and the bolt handle configured for scope clearance.

Upon receiving, the rifle was carefully broken in. Groups resembled buck shot, but this was attributed to barrel newness and lack of a proper load workup. Bore inspection revealed rifling button chatter marks, so a NECO fire lapping kit in 6.5 caliber was obtained and the bore lapped as per instructions. This slicked up the bore somewhat, but the grouping still wasn't what was desired. Took the gun back and had the barrel shortened to 23", thinking a shorter and stiffer barrel might help. By this time, some 250 - 300 rounds had been fired. The cases always seemed a little stiff on bolt opening, but since it was tight chambered, always figured it was just due to close tolerances. They also developed enlarged primer pockets and case life was short - 6 or 7 reloads max.

The groups got down to where 3 shots would make a clover leaf, then 2 would be wild fliers. Thoroughly disgusted, while cleaning the rifles after the latest range session I decided to slug the bore and determine if there were tight and loose spots in it. There were 3 tight spots and 2 loose spots as the slug was driven down the bore. The recovered slug showed 4 lands were cut nicely into the lead slug, but 2 hardly engraved it. Grabbing the micromoter, the slug miked at .2577" - WHAT????? A half dozen measurements made rotating the slug and up and down its length all said basically the same thing - .257"! The muzzle of the barrel was miked and sure enough - .257".

Called the gunsmith to assure he was in his shop, took rifle and slugs and hotfooted it the 10 miles to his shop. Told him what I suspected and he looked at me like a redheaded bastard step child! THEN - HE miked the bore, looked at his applied roll stamp on the barrel with his name and "6.5x257 Ack Imp" engraved on the barrel chamber just ahead of the receiver ring. In a quiet voice he said "Well, it's sure a .257 bore!"

My knees got a little weak when thinking of all the rounds that were fired through that rifle, squeezing .264 bullets down to .257 - WOW! All I can say is, thank you ever so much Husquavarna, for making an action that could actually fire swadge jacketed bullets down .007" and never miss a lick! Man, I'll bet there's a free-bore throat in that barrel that Weatherby would be proud of!

Well, the upshot is a new barrel blank was selected and carefully miked. The new replacement barrel will be finished and installed in exact replication to the old and ready for my pick-up next Friday, 10-12-0l. I had taken an extra lead slug along and it proved the new bore was consistent from end to end with good lands and grooves, also miking at .2638".

Stay tuned for the rest of the story.....................
Keep below the ridgeline!

Edited by: kdubaz at: 10/6/01 6:20:19 pm

V.I.P. Member
Posts: 360
(10/6/01 12:33:52 am)
Reply | Edit | Del Re: Let Me Share With You!!
EEK Gads! Bet that barrel heated up quick.

I hope you get it straightened out.


Senior Chief Moderator Staff
Posts: 1757
(10/6/01 8:49:08 am)
Reply | Edit | Del Re: Let Me Share With You!!
Still doesn't beat the Rifleman story where the guy wrote the NRA about "excessive recoil" from his 7.7 Arisaka, they had him send it in, and found he was shooting 7.7 through his action that had been rebarrelled with a 6.5 barrel!!!!

Fire swaged JACKETED bullets from 7.7 down to 6.5...NRA technical staff did it too (From next door, with a LONG string tied to the trigger, probably ...)to test and had the recovered bullets to prove it... They were pretty darn LONG...

That old Arisaka action is STILL the strongest ever showed NO adverse reaction.
I'm so PROUD to be an AMERICAN...

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