Can anyone explain in basic terms how action feeding is modified? For instance, how do you determine how much metal to remove from rails to allow a cartridge to feed properly ? say from a 416 rigby to 470 mbogo? 460 weatherby to 500A2? For a wildcat that uses a larger diameter bullet in the case that the rifle was original built for (you have already sent action out and a new, larger bore barrel has been fitted to the action) -- how is the feedramp alteration figured? is this by removing tiny amounts until smooth feeding is accomplished or do you "just" allow feeding, taking into consideration wear will slightly open the tolerances? Also, what about feeding from a wildcat where you have necked down the case to shoot a smaller diameter bullet such as a 6.5 X 284 or a 300WSM to a 6.5 or maybe 257? It seems that going to a smaller diameter neck / bullet would probably feed just fine and the "tricky" ones would be the wildcats where you increase the original cases mouth ? Do any basic gunsmithing books discuss how to alter feeding, rail modifications, ramps, cartridge followers, etc. ? How did you guys learn this stuff ?? I am pondering two future projects, one going down in bore size and the other increasing bore size - thanks for any ideas - KMule

I could tell you but it would take about 23 years

KMule,

It is an acquired skill. The best approach is to remove the firing pin and watch what happens when you try feeding a round from the magazine. Look carefully at every aspect and position of the round as the bolt and cartridge is moved forward.

In an ideal world, you would want the cartridge to emerge out from under the feed rails and slip under the extractor or into alignment with the bolt face as the cartridge is climbing the ramp towards the chamber. The worse possible scenario would be to remove a little too much material and have all the cartridges pop up into the feed port at once.

Correcting feeding problems can be as simple as a couple of well placed file strokes, or, as complex as re-machining the bottom radius of the actions feed rails. Go slow and good luck...

Malm

[QUOTE]Originally posted by KMuleinAK:
[QB]Can anyone explain in basic terms how action feeding is modified?

The Mauser Bolt Actions, by Jerry Kuhnhausen and Mauser M98 & M96, by R. A. Walsh are good
(basic) Gunsmithing books !
Good luck!

Good one D'Arcy!!

The first trick is to screw up about 20 nice actions.........

Take one old butchered, no good action and mill away all but a little bit of rail all the way around. THen rebuild it using metalic epoxy (MSC has bronze, copper, stainless, and tungsten). Then carve away until it feeds perfectly......then try to duplicate it in a good action.

The best thing you can do is buy an original Mauser in any original caliber and then buy a box of MILITARY ammo for it and make feeding dummies out of them. Then STUDY every single motion, action and reaction and *understand* how and why it works the way it does.

Big bores work by the bullet hitting the feed ramp. Bottlenecks act off the shoulder. A Mauser that feeds right takes the same energy to work the bolt in both directions. It's hard to do.

Thank you for the responses; I am aware that this is not something one jumps into and suddenly knows how to do it properly. Thank you - KMule

KMule,

What are you contemplating, exactly? Some of these guys could probably point at a few things more specific to you particular need if they knew. You might talk to Dave Caboth out in Wasilla at Notro Gun Works, he'd give you some pointers and maybe suggest some referance materials on the subject as well.

Good luck, and go slow. How well you understand what is happening during the feeding process and how well you identify the problems will determine alot of how well you can do to solve the problem(s).

I have heard of formulas to figure rail and box configurations for a particular cartridge but havn't heard anyone comment on here about them and how they work. Dave was the one that mentioned it to my dad a while back.