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Practically Shooting

New Project Underway: .260 Ackley Imp


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I have this Savage .308 I haven't used much.  I don't think I've shot it in two years. 


I've also had a desire for a rifle in .260 Remington since the early 90s when it was still the wildcat 6.5-08.  


So I quit putting it off and ordered a pre-fit "X-Caliber" barrel in .260 Ackley Improved.  I went with the improved version since I can't see ever buying factory ammo for it, and might end up forming brass from 7mm-08 or .243.  If I'm going to be messing around with that, I might as well blow the shoulder forward and gain a few fps.  


With 120-140 grain bullets, the AI version allegedly comes within 100 fps or less of the 6.5-284 that burns a lot more powder (and barrels).   That puts it shooting 140s right at 2900-2950 fps, which seems to be a sweet spot for accuracy in the 6.5MMs. It seems to be one of the better AI'd cartridges.  


My plans for this will be long range shooting, particularly 1,000 yard F-Class.  It won't be lugged over hill and dale, so I went with a hefty contour (1" at the muzzle) and 26" long.   I hard a hard time choosing between 26" and 28", but went for the "shorter".  Sometimes when you get too heavy, the rifle feels like it's going to drop over the front of the front rest.  


Wish me luck.


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Entertaining myself with numbers since the barrel isn't here....

Some ballistic apps seem a little unbelievable to me, but the one from Applied Ballistics seems pretty good and matches my guns pretty close.  It is done by Berger Bullets' ballistician.   These figures came from there  

The .308 load I've been using is about the best I can do for distance with a .308.  It uses a Berger 185 "Juggernaut" bullet with a BC of .540 G1* and .283 G7* at 2610 fps. 

My plan for the .260AI is a Berger 140 LR (BC of .303 G7) at 2900. 


At 1000 yards, with a 10mph full value crosswind:


Drop 36.17 MOA  Wind Drift: 6.48 MOA Remaining Velocity: 1264 fps  



Drop 27.0 MOA  Wind Drift 4.79 MOA  Remaining Velocity: 1547 fps 


The .308 load goes transonic at 1141 yards  

The .260 goes transonic at 1409 yards. 


Shoot fire, I won't have to do anything but lie there and load the rifle!   This will make it EASY!




*G1 is the bullet profile that best matches bullets shaped like a .22LR solid.  G7 is a closer match to most BTHP or BTSP bullets, especially the longer range designs.   One might expect G7 would be the standard, but G1 gives a higher number, so naturally manufacturers use it.  

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  • 2 weeks later...

Slowly but surely.    

No barrel yet.  I do have some brass, some bullets, and a seating die is due to arrive romorrow. 

Brass is Lapua .260, and some Win .243 to open up using mandrels I ordered.  Lapua is consistent, but supposedly heavy.  The Winchester should be thinner and hold more powder. 


The only bullets I've ordered so far are some Berger 140 LR.  I have most of a box of Hornady 140SP (I have a 6.5x55 Swedish Mauser) that I will load to fireform  brass to the improved chamber. 

I keep reading that the .260 to .260 AI fireforming process has a strange trait of making good groups.  I'm not sure if I'm glad I read that.  I will probably get the one barrel that won't, then I'll be too worried about reloading the formed cases I'll never get around to shooting them.  


The seating die coming tomorrow is a Wilson chamber type (benchrest type).  With the .260 AI being a wildcat, I found dies from the regular companies cost as much as the Wilson's and often quite a bit more.  So...why not? 


I need to order a barrel wrench.  It can be done without one: some drill or welding rod dropped in the barrel nut's grooves, engaged by a regular twelve point wrench- size 1-1/16 I think.  But I think I'll use the proper tool this time, partially because I'm also ordering a new barrel nut (thats longer to engage more threads).  A new recoil lug is needed too, but I'm having some trouble deciding. I can get them in the usual oversize thickness of .250"... or thicker, like .300" up to .500".  I don't know if a super thick one would actually help, but I can't see how it would hurt.  The thing is, I don't know how much space I'll have under the nut. How much determines how thick I can go.  This may have to wait until I have the barrel and all in hand to do some measure-izing. 


And a Savage barrel swap goes quick because everything is out there, and seldom needs a gunsmith. 

Yeah, quick.   Patience is a virtue. 


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That one is a Berger 6.5mm/.264 140 grain BTHP Hybrid Target.  Bc is .618 G1 or .317 G7.  

For comparison:

The Sierra .30 cal 168 BTHP MatchKing is .462 G1 or .218 G7. 

The bullet I have been using in F-Class with my .308 is the Berger 185 BTHP LR "Juggernaut".  It is about the highest BC bullet you can get a .308 to handle.  The  bc figures for it are .540 G1 or .283 G7.   Those are some incredible numbers, but as you can see, a 6.5 bullet beats it easily.  Plus, I hope to send that 6.5 bullet almost 300 fps faster. 

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  • 11 months later...

Yesterday was one year since ordering this barrel. 




Full disclosure, I did make a change along the way.  I contacted him in May and changed the order from a 26" to 28".  This added the complication of having to use a different blank manufacturer to get that length.  Since my blank hadn't been ordered yet however, it should not have made any difference.  


And that's the only contact I've had with him since ordering.   I tend to get my questions out of the way up front for things like this, place my order, then stay out of the way and let them work.  He did post an update on his website last Sep.  It seems he added an employee and took on more work accordingly.   The employee didn't work out, so he was let go, but the owner still has the orders to fill.  


I can understand that accounting for some more time.  Maybe not this long.

Perhaps I should've emailed quite a while ago, but as I said, I hate ordering something them bugging them about it.  


Then I saw this bit of news.   The blank is/was coming from X-Caliber.  At the time I ordered, they only sold blanks and no threaded and fitted ones.

Now they sell them.

And in the contour I really wanted rather than the one I sorta want.  

Lead time is 6-8 weeks.


I gave him until yesterday, then sent him an email wishing him a happy anniversary.   We will see what I hear.  






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  • 1 month later...

I got a reply.  My order was found in the "Completed" file, like several others have been.  He says he is going to jump on it and get it out by the end of the week. 




I guess that's the system.   You learn some orders were never completed even though they were filed as such.   More than a couple of them.  So what do you do?  

I guess you just wait until you hear from someone looking for their barrel.  And don't watch your email very close either. Why bother with that?

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  • 2 weeks later...
  • 5 years later...
  • 10 months later...

It's about ten days from marking another year into this project.  There is progress to report.  Not much, but its still progress.


Last week, I ordered the barrel nut wrenches to take the old barrel off the Savage.  This past weekend, I attacked it.  

And it almost took the whole weekend to get it off.  That nut was TIGHT.

I could not get the barrel vise tight enough to hold the barrel from turning while I tried to wrench off the nut. I worked on it Saturday until I got too frustrated and made myself quit before I did something stupid.  I left it soaking in Kroil overnight.


Sunday, I approached it with anger. I dusted the vise blocks with powdered rosin, tightened the halves down with a 5/16 Allen wrench, then put a cheater bar over the Allen and gave all all those bolts some more.   Barrel nut wrench on, 1/2" breaker bar on that, and a pipe over the bar.   Heave!

Nothing...nothing...it's turning!  Aww, it's turning in the vise again.

That's it.  I had ordered another barrel nut with the wrench set, making the original nut expendable.

Dremel, you're up.

Using a cutoff wheel, I slotted the barrel nut front to rear, stopping about 3/16 from the recoil lug.  I didn't want to go any further for fear of cutting into the lug.  Two slots, about 100 degrees apart.  

Back on the bar.  Nothing.  

Dremel powered up, and a third slot is cut.

This attempt, it finally broke loose.  


As i turned the barrel nut off, I was getting "crumbs" coming out of the threads.   Corrosion.  Why and how, when the rifle had seen little use and showed no corrosion elsewhere, I don't know.  It must've been factory installed. 

I spent the next hour cleaning up the receiver threads.

I examined the Savage bolt once more.  When I was shooting that rifle, it was leaving fired cases in the chamber.  I'd open the bolt and the extractor would pull off, leaving the case in the chamber so I'd have to poke it out from the muzzle with a cleaning rod.  Only when I backed off the powder charge by five grains, when it was already a moderate charge at most, would the empties reliably extract.   OK, so either the extractor isn't working properly or something is up with the chamber causing higher pressures.  I would later learn weak extraction is pretty common in these.  

So I looked at why.  

It was easy to see.  The extractor barely hooks the cartridge rim.  It's not the easiest to measure, but it was grabbing only .024" of the rim at its deepest part.  And that would only be if the case was tight against the boltface on that side.  It was possibly only getting around half that.  It's the way the extractor is machined; it couldn't go on any more.


So, disgusted again, I put it all aside and cleaned guns.  






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