I’m contemplating upgrading my .243 Browning B78 High Wall to a 6.5x55 AI Mauser, with a new 28 inch heavy barrel. I’d greatly appreciate feedback from anyone with knowledge and experience regarding whether or not such a 40 degree shoulder angle IMPROVED case (which has noticeably less taper than the parent case) would result in noticeably more frictional force and effort when being manually inserted into such a single shot's chamber.
Cheers from ‘down under’
Ross.

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One clean, humane shot for all ferals !

As you are posting another thread specifically for this question, I will offer my experience with straight-walled and nearly straight bottle-necked cartridges, in single-shot actions.

I have a 30 Herrett (.012" taper) a 6.5JDJ (.013" taper) and a 358GNR (.011" taper). All of them are fired from single-shot, break-action rifles/pistols. None give any difficulty whatsoever when inserting into, or extracting from, the firing chamber. Perhaps more to the point, pistol cartridges, which are truly straight-walled (no taper at all) do not present any problems with chamber clearance when used with single-shot actions. Honestly, you need to worry more about case taper with the various repeating/semi-auto actions than you do when you're inserting them one at a time!

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Ask me about QDMA.

I see no real advantage in the so called "improved cartridges". I fell for it and I have a few of them. Overall they are just a small bother and fun for some.

One of my rifles is a .219 Improved Zipper built on a High Wall action. I FL size all loads for it. They just chamber easier.

Same with my 06 Imp. and the 375.

If you feel that you will have something special with the Imp chamber then do it and enjoy yourself. Don't let me spoil your fun.

Jason, thanks also for clarifying my query about not having to worry about manually feeding the relatively straight-walled 6.5x55 Improved case into my old B78’s chamber. I’ve often stated that the members of this particular forum are fantastic for openly sharing their relevant knowledge and experience – keep it up !



Savage99, according to the following article, (http://shootersforum.com/showthread.htm?t=5813) some cartridges are ‘improved’ more so than others when their shoulder angle, taper and powder capacities are altered. Apparently the 6.5x55 has the 4th best velocity gain - supposedly offering a 13.7% increase over the standard factory round with a 140 Gr projectile.


In contrast, “Right on the borderline of our rule of thumb for getting involved in is the old-time .219 Zipper, no longer being chambered for. The factory load with a 55 gr. bullet is 3300 fps, and the Ackley can achieve a velocity of 3500 fps, a gain of 6.0%. This is a rimmed cartridge and just about obsolete, with very little demand”.


For consideration, apparently standard US factory loaded 6.5x55 cartridges are purposely loaded well within their maximum powder capacity in order to be safely fired in the old ‘weak’ M94 type military rifles. To be fair, the Improved 55’s rather substantial 13.7% velocity gain probably stems from a near max powder load fired in a long barrelled modern ‘stronger’ action rifle.

Cheers, Ross.

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One clean, humane shot for all ferals !

Hello Ross,

I started out handloading in 1953 and when I saw my first High Wall I just had to have one. They were dear and scarce in the 60's. I found one smithed by the late Floyd Butler with had been an R2 Lovell that someone else had rechambered to .219 IZ. I bought the rifle along with the dies that came with it. It was the only one around.

Of course some other chambering would have been easier. These days what with the lack of new .219Z brass I make them from 30-30 or .225 Win.

Excuse my lack of enthusiasm for the so called "improved" chamberings. I knew Lysle Kilbourn personally and own improved chambers. I fell for it to. Do it if it gets you going.

On the practical side the 25-06 is only .007" less in bullet diameter and easy to find here. There are others.

Have fun.

Savage99, your pictured High Wall certainly looks like a much used and no doubt treasured firearm - beautifully constructed and a real pleasure to shoot. How old's the rifle and what's the trigger like ?
Cheers, Ross.

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One clean, humane shot for all ferals !

I would guess that the rifle was built in the 1930's. It indeed is a treasured rifle. I have shot many chucks and other pests with it. The trigger is excellent and the rifle stays sighted in, which is #1, and shoots excellent groups.

I shot it at the range last May 3rd and it made a 1/2" two shot group at 100 yds and 1.5" with two shots at 200 yds.

I had Floyd make up some other custom rifles for me in the 60's after I found this one.



Here is a link to some discussion of the late Floyd Butler.

http://www.24hourcampfire.com/ubbthr...opics/110535/2

I will agree with the others that it's doubtful you'll have any issues chambering the round. I have 1885's in .45-90 (long straight case), .454 (short straight case), and .270 WSM (sharper shoulder angle and less taper than standard .270). All chamber easily and smoothly. I do have to make certain to put a small taper crimp on the .45-90 to ensure smooth chambering (the mouth can catch or drag if not cleaned up), but that's a far cry from the 6.5x55 Improved cartridge. :-)

Savage99, thanks heaps for the referral to the inter-change between Ken and Don - in turn, people such as Floyd would have been a real treat to talk to. Much like your High Wall, very much appreciated and cherished.
Cheers, Ross.

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One clean, humane shot for all ferals !

Here is a picture of the butt stock of a rifle crafted by Floyd Butler. The curl at the cheekpiece and the bottom of the grip were his trademarks. He was an artist with walnut.