For feeding through a bolt action.

If one were to only use this criteria, which cartridge by virtue of case design would be the most slickest feeding of them all?

Preferably .40 cal and over.

Beltless? Lots of case taper? Modest shoulder angle?

404 Jeffery meets your over-40-bore criterion so that makes it easy.
This is not to say that it cannot be improved upon for slickness of feeding,
but in practice, with standard, non-wildcat cartridges, that's the one.

A .410/404 Jeffery Rimless Nitro Express in the works, with slightly smaller shoulder diameter (more case body taper),
and a slightly smaller bullet diameter, will be even slicker feeding.

The 404 Jeffery really is odd in having minimum case body taper, right at the limit of what P.O. Ackley would allow.
It makes up for that with the long, sloping shoulder and neck.

Plus, the 404 Jeffery case head is the largest diameter that can be made to stagger-stack in the available magazine box widths,
to Mauser-Cosine-Law perfection.
Anyone claiming the .416 Rigby/Weatherby-based casehead is sacrificing perfect box geometry for a make-do staggered stack.
But if a straight-line stack is used, they may have justification for larger casehead and relatively smaller bullet.

I have not decided whether presence of a belt is a hindrance to feeding slickness.
I really don't think it could be much of a help,
other than contributing to case body taper as an abrupt ~.010" step-down per side or ~.020" abrupt diameter change,
and that amounts to a tiny 90-degree shoulder "hemi-angle" or pseudo-flange/rim,
neither of which are conducive to slick feeding.
Better to go beltless and use case-body taper and subacute shoulders and long necks,
and bullet diameter smaller relative to case head siize for "slick feeding."


There is more than one way to skin a wildcat.
Riflecrank Incurable Permanente

Since 40 calibre and bigger then the 416 Rigby and 416 Wby.

Simple reason. Feeding will always be more reliable and especially with blunt nose bullets when the diameter of the chamber entry is bigger than the bullet diameter and the more the better.

^So out of the available factory rifles, a CZ in 416 rigby would have a pretty good chance of good feeding with flat point solids?

Most of the CZ feeding problems I've read about seem to involve 458 win or lott. Rounds without any shoulder or much hody taper.

I have a CZ 458 lott. Never had a miss feed.
Can cycle the bolt fast or slow and in between. Slick as a whistle.

quote:

Originally posted by Quickstrike:
^So out of the available factory rifles, a CZ in 416 rigby would have a pretty good chance of good feeding with flat point solids?

Most of the CZ feeding problems I've read about seem to involve 458 win or lott. Rounds without any shoulder or much hody taper.

If all was well then a Mark V Wby in 416 would be better because of the in line feed.

But if you consider cost then a CZ would leave a lot of money left and I reckon a CZ sent to American Hunting Rifles (who post here and seem to have CZs as a speciality) then what you got back would be as reliable as you could want.

I settled on the 404 Jefferys and actually the .416 Rem. is hard to beat, The 404 requires one of the better gunsmiths to make it feed in a Mauser..Ive seen many that wouldn't function..The best option for the 404 is the Win. mod. 70 in the Rums calibers that are based on the 404 case, the hard work is done for you.

I love my 416 Rem. Only time it's failed me was when I shortstroked it and you can't blame the rifle or the cartridge for that.

As always on AR I can't stick to the OP's options. I would choose a 375 H&H and load 350g Woodleigh HD softs to 2300 fps to give you close to .40 caliber power. Nothing feeds like a 375 H&H.

Like Chuck says a .375 H&H is a pretty dam slick feeding rifle, at least my 2 Winchester Mod 70's are. I also have a 400 Whelen that spits 400 grain bullets at 2140 fps, holds 5 down plus one in the pipe and feeds slick like a 30/06.
Just saying...
The shape of the 404 Jeffe always looked to me like it would feed like gas through a funnel, similar to the .375 H&H

Of all the over-40 cal cartridges, the 416 Rigby feeds the best "out of the box", in the CZ's at least. Even with feeding work, the Rigby is easier to get to feed well than the 404 or anything else.

My Sako in 416 Rem Mag feeds as slick as sausages down my German Shorthaired Pointer's throat.

My favorite is the 416 rem mag it's about as predict as it.gets .My model 70 super grade is slick as a button !My.model 700 rem are slick too in 416 rem mag !

I have owned three of the CZ 550 Magnums in .416 Rigby, and only one in 404 Jeffery.
They all fed well out of the box with round-nose and spitzer bullets.
My one 404 Jeffery would feed the flat-nose solids just as well,
but I had some balkiness on the .416 Rigby's, only with flat-nose solids.

The CZ-USA "factory" 404 Jeffery would hold 5 down in the box and not too tight to allow a sixth in the chamber.
The semi-custom nature of that chambering back when I got it,
early on, I think means that some extra attention was paid to the feed work.

The .416 Rigby's were/are produced in much greater quantity than the 404 Jeffery.
Some CZ .416 Rigby's would hold only 3 down in the box with room to spare, but not enough room for that 4th cartridge.
Some would hold 4, plus barely enough room to close the bolt and get 1 in the chamber.
This might be due to whether that .416 Rigby got either the internally ribbed sheet metal box stamped "375H&H"
or the smooth-sided box stamped "458WM."
If not that, then I do not know what the reason could be.
Wham-bam-thank-you-mam.

My old Ruger RSM .416 Rigby feeds flat-nose bullets as well as spitzers,
and holds only 3 down plus 1 in the chamber, easily,
in an apparently shallower box than found on the CZ.

The .416 Rigby owes its good feeding ability to the huge amount of body taper it possesses.
First glance is deceptive with that modern-looking, 45-degree shoulder,
not even P.O. Ackley would exceed 40 degrees,
but the .416 Rigby has a big 0.022" of diameter taper per inch of case body length.

The 404 Jeffery has very little case body taper,
which is deceptive to the eye glancing at that antique 8.5-degree shoulder and extra long neck.
But the 404 Jeffery has only 0.008" of diameter taper per inch of case body length.

What is the optimum case body taper for feeding?
That may not be as important as the overall effects coming from shoulder-to-neck and neck-to-bullet-meplat.
P.O. Ackley settled on .0075"/Inch as a minimum for his multi-purpose analyses,
even if feeding might not have been high on his list.
The 404 Jeffery barely beats that at .008"/Inch.

One fact is an undeniable truth.
The 404 Jeffery is the biggest case head that can be made to properly fit in the staggered-stack box, Mauser-style,
of the available boxes, Winchester, Ruger, Mauser, CZ, Dakota, etc. etc.
Wider boxes just won't fit into the action, unless special, over-size actions are made.

The feed-job tricks to get case heads bigger than 404 Jeffery to fit, retain, and feed from the available magazine boxes are many.

The likely reason that so many think the 404 Jeffery is not as slick a feeder as a .416 Rigby is because
so often a 404 Jeffery is made to fit in an action meant for a 30-06-sized cartridge.
It should go into a Mauser 98 Magnum-sized action.
Then the 404 Jeffery is slicker than a .416 Rigby that is made to go into a box too small for it.

But the squeeze of the .416 Rigby into a Magnum Mauser involves less drama than the squeeze of a 404 Jeffery into a standard M98.

Rigby started off with the Magnum Mauser meant to fit their 400/350-2.75" Flanged cartridge.

Mauser designed it to handle the longer cartridges so the standard 98 would not be opened in length and weakened, a common practice.
Mauser did not want guilt by association with their action when botched jobs failed.

Then Rigby tried turning the rim off of a 450/400 NE 3-Inch, the ".400 S. Jeffery" as an attempt to keep up with the Jefferys,
who developed the 404 Jeffery basically the same way, but with a bigger bullet diameter to let off pressure with old Cordite.
The 404 Jeffery hit the field by 1905.

Rigby chambered at least one rifle for their weak attempt at a copycat to the rimless Jeffery cartridge.

Rigby soon saw the light on the slant-box/flanged combo and developed the rimless 350 Rigby Magnum.
One source says the base diameter on that was .519".
Then Rigby decided to one-up Jeffery by creating the .416 Rigby with a greater case diameter as well as a bullet diameter increase of not so much as had been done by Jeffery to provide pressure relief for the 404 Jeffery.

So the .416 Rigby "accommodation for old Cordite pressure" was done by a little bit of this, case volume increase,
plus a little bit of that, bullet diameter increase, but not so much of the latter, going from .410 to only .416.
Voila! No longer a Jeffery copycat!
But now too big for the action that the 404 Jeffery is perfect for,
the action that Rigby ordered initially for skinnier cartridge cases.

But in this imperfect world, we continue to shoe-horn the 404 Jeffery into the standard M98,
and the .416 Rigby and larger get shoe-horned into the Magnum Mauser.

Rigby was shoe-horning the .416 Rigby case into the Magnum Mauser 98 by 1911.
that action box was designed for a smaller head size.

Like Chuck375, if I may pick a smaller-than .40-caliber "slickest feeder,'
I will now pick the .333 Jeffery Rimless.
Base diameter .540"
Shoulder diameter .496"
Pointier meplat, even with a flat-nose solid.
.333-caliber/300-grainer SD = .386

1908-vintage bullets at 2200 fps would work, even today.
Some modern bullets and powders would require rewriting the minimum caliber laws in Africa.


Oh. Yes. The .375 H&H has always been a slick feeder too.
Another reason for its great success.

If the shoe fits, wear it!
Or for a little time and money you can get those cowboy boots stretched to fit!


There is more than one way to skin a wildcat.
Riflecrank Incurable Permanente

people have sung the praises of the 375HH for quite a long time for feeding and extraction. IMHO so much of this depends on the gun being of proper tuning.

I wish Tom Burgess were still around to comment on this. I would love to hear D'Arcy Echols thoughts as well. I have a feeling that there really is no absolute best, or at least no round that a human being can absolutely perceive as feeding the best. The different actions and cartridge lengths must be taken into acount as well. Long vs short bolt throw etc. Wide meplat flatpoint bullets tend to throw in a monkey wrench, so maybe they shouldn't even be considered. I have a feeling that a 416 Ruger feeding from a properly optimized Model 70 would be a strong contender.

Matt,
Some good points there.
At a certain point of meplat size versus cartridge diameter, some of the meplat is going to lie below the top of the magazine box at the start of the feed ramp.
There is no way in hell it is going to start up that feed ramp when the bolt is pushed forward.
The bolt and cartridge come to a complete, dead-stop jam.
Some flat noses will work until the meplat gets above a certain percentage of bullet diameter.
Even if it does start up the feed ramp it will cause the cartridge to angle up and/or diagonally
and jam the bullet nose inside the action ring or on the edge of the chamber instead of entering the chamber.

Michael McCourry showed by his "McCourry Ballistic Institute" testing that about 65 % of bullet diameter,
certainly below 70%, is optimum for penetration as well as getting a rifle to function at all, i.e.,
to get it to feed.

I have heard it said that D'Arcy Echols will not even consider a flat-nose solid feed job. Smart man. That makes his life a lot simpler.

There is more than one way to skin a wildcat.
Riflecrank Incurable Permanente

I find myself lusting for at least one rifle in every chambering mentioned.

404 Jeffery
416 Rigby
375 H&H


What about .45 cal and over?

450 Rigby and 450 Dakota?

505 gibbs vs. 500 A-square?

Interesting discussion, please continue!

Hell, why stop at .500. Enjoy the 550 Magnum, 577 T-Rex, 600 Overkill.

The 505 Gibbs is another problematic cartridge to get to function properly in most actions. It can be done, but a lot of work to make it right. It works well in larger actions like the GMA African Magnum or the MRC PH.

The 500 A-Square works well in the CZ 550 Magnum action, with work, but getting brass is the hard part with that cartridge.

Don't even think of trying to put one of these in the Winchester; I won't do it.

^Because after shooting my 458 lott, I think a 500 a-square loaded down to about 2000-2100 fps will probably be my limit.

Does the slight rebate of the a-square cartridge pose problems with the bolt face overriding the round?

I am not a "rifle guy" as in, I really do not care if is push feed or pull feed or controlled feed or out of control feed - just so long as it feeds.
I have use Mauser's, Model 70's, CZ's, and an HS Precision in .375 HH and .416 Rigby. All fed well and smoothly. If I could stand the recoil everytime, I would use a .416 Rigby on everything. However, until I get my suppressor on my .416 Rigby, it will be a .375 HH for most hunting. It feeds, shoots most ammo well and is easy to use.

Feeding is partly action and mostly the guy pulling the bolt.

If you want perfect feeding - buy a Blaser. It is idiot proof contrary to jamming Mauser's and push feeds. That is what I am moving to.

quote:

Originally posted by Quickstrike:
I find myself lusting for at least one rifle in every chambering mentioned.

404 Jeffery
416 Rigby
375 H&H


What about .45 cal and over?

450 Rigby and 450 Dakota?

505 gibbs vs. 500 A-square?

Interesting discussion, please continue!

The three you listed are all you need. Any of the 450 whatevers are a beast to shoot.

quote:

Does the slight rebate of the a-square cartridge pose problems with the bolt face overriding the round?

The rebated rims are really a non-issue. I've never had problems with any of them, at least because of the rebate.

quote:

Feeding is partly action and mostly the guy pulling the bolt.

No truer words were ever spoken.

Just build a formula for feeding and see what the answer is:

cartridge length, cartridge diameter, angle of change from magazine to chamber, bullet shape/point diameter, chamber breech diameter.

Apply the measurements and you'll end up with a number which will provide a quantitative difference between cartridges.

Lot of flat out statements claiming one caliber over another is all reliable as if some kind of black magic is involved..

Caliber has little or nothing to do with reliability with any cartridge..Some fail and some never fail..

Reliability has to do with who did the work on the gun or which factory rifle you happen to get and that's somewhat of a crap shoot. who tunes it up is whats important, who cares for the gun, who has the needed knowledge to keep a gun shooting..IMO its all about owner responsibility.

A custom rifle should be 100% reliable, Some are and some are not, some leave the custom shop without a shot being fired or tested..

A factory rifle that should pass inspection, but often it is not. Factory rifle especially needs to be tested for feed and function, and probably tuned by the buyer or sent to a reliable smith, then its the hunters job to thoroughly test them all before hi-ing off to Safari or whatever..

There are few legitimate reasons for failure to feed,function, and shoot well by the time of your hunt, I see that as the hunters responsibility, and proper matinence pays big dividens as well.

Ive seen so many guns go south from lack of knowledge on Safari, and from bad advise by even some of the best rifles on the market, both custom and commercial.

400 hh ...
416 rem
416 taylor

or 458 Accrel

but, really, the 577 NE in a Searcy feeds the best

quote:

One fact is an undeniable truth.
The 404 Jeffery is the biggest case head that can be made to properly fit in the staggered-stack box, Mauser-style,of the available boxes, Winchester, Ruger, Mauser, CZ, Dakota, etc. etc. Wider boxes just won't fit into the action, unless special, over-size actions are made.

The feed-job tricks to get case heads bigger than 404 Jeffery to fit, retain, and feed from the available magazine boxes are many.

Not necessarily. I have Duane Wiebe 4MJ bottom metals on my two FN commercial M98 actions that easily accommodate 3-down cartridges of my 338 Lapua derivative wildcat cartridges.
The unimproved .423 caliber box has sufficient crush space for the 4th cartridge to be easily picked up under the extractor.
The improved .500 caliber has sufficient crush space for the 4th cartridge to be picked up under the extractor with a bit of thumb work on my part. Some day I'll likely add a Pocket or Rigby style floorplate to eliminate the extra thumb work required to pick up the 4th cartridge.

quote:

Michael McCourry showed by his "McCourry Ballistic Institute" testing that about 65 % of bullet diameter, certainly below 70%, is optimum for penetration as well as getting a rifle to function at all, i.e., to get it to feed.

68% +/- 1º is the optimum penetration sweet spot.
At 70% and above of bullet diameter the feeding becomes nigh on impossible though the trauma imparted is enhanced greatly.
At 65% and below within mass bullet stability is little better than a RN solid.

quote:

Originally posted by capoward:

quote:

One fact is an undeniable truth.
The 404 Jeffery is the biggest case head that can be made to properly fit in the staggered-stack box, Mauser-style,of the available boxes, Winchester, Ruger, Mauser, CZ, Dakota, etc. etc. Wider boxes just won't fit into the action, unless special, over-size actions are made.
The feed-job tricks to get case heads bigger than 404 Jeffery to fit, retain, and feed from the available magazine boxes are many.

Not necessarily.


Yes, absolutely and mathematically "Mauser Co-sine Law" NECESSARILY.
I have the one-piece bottom metal that Duane Wiebe makes for the 500 Jeffery.
I used it on the 500 Bateleur (.510/338 Lapua Magnum-Improved-2.7" case length).
It is too narrow for that case head, let alone the even bigger 500 Jeffery case head.
But it is made to work, and does work well enough,
but don't ever expect it to be as slick as if the 404 Jeffery case head were being used.


I have Duane Wiebe 4MJ bottom metals on my two FN commercial M98 actions that easily accommodate 3-down cartridges of my 338 Lapua derivative wildcat cartridges.
The unimproved .423 caliber box has sufficient crush space for the 4th cartridge to be easily picked up under the extractor.
The improved .500 caliber has sufficient crush space for the 4th cartridge to be picked up under the extractor with a bit of thumb work on my part. Some day I'll likely add a Pocket or Rigby style floorplate to eliminate the extra thumb work required to pick up the 4th cartridge.

We are not talking about mere depth of magazine and capacity in number of cartridges here.
It is about the ability to pack three cartridges into the box, stacked with stagger,
so the center-lines of the cartridges pass through the apex points of an equilateral triangle, all equidistant from each other.

quote:

Michael McCourry showed by his "McCourry Ballistic Institute" testing that about 65 % of bullet diameter, certainly below 70%, is optimum for penetration as well as getting a rifle to function at all, i.e., to get it to feed.

68% +/- 1º is the optimum penetration sweet spot.
At 70% and above of bullet diameter the feeding becomes nigh on impossible though the trauma imparted is enhanced greatly.
At 65% and below within mass bullet stability is little better than a RN solid.

That sounds right.

BTW, saying the 378 Weatherby has a rebated rim is a bit of quibbling. It is a minor rebate.
And Weatherby usually feeds those big cases from an in-line stack that eliminates any quibbling.
Their extra-capacity "dropbox" holds 3 down in a vertical, in-line stack.

But there are other cases where the rebate is much greater and that can cause some significant feeding issues,
for anybody but a magician, of course.


There is more than one way to skin a wildcat.
Riflecrank Incurable Permanente

quote:

Originally posted by dogcat:
I am not a "rifle guy" as in, I really do not care if is push feed or pull feed or controlled feed or out of control feed - just so long as it feeds.

LOL I like that!

quote:

Originally posted by chuck375:
As always on AR I can't stick to the OP's options. I would choose a 375 H&H and load 350g Woodleigh HD softs to 2300 fps to give you close to .40 caliber power. Nothing feeds like a 375 H&H.

.300 H&H feeds better....

I just got my Dakota in .400 H&H and it feeds just like my .375 H&H which is to say great.

It is certainly easier to build a 404 on a true magnum action IMO, and has always been my preference, A 404 on a 98 can be a blivit, 10 lbs or s--t in a 5 lb. bag.

Wesley Richards built a few 404s on 98 actions and the one I saw and played with was a really nice gun, fed well and functioned properly, so it can be done, but yes, its a headache. The problem is so many gunsmith claim to be able to do this but most of them if you try hard enough to jam their gun, you will be successful..A DG rifle must be 100% failproof, and that's hard to live up to as humans are frail..

Be sure and have a written money back guarantee as to feeding all brands of ammo, both softs and solids and flat nose solids. see who runs backwards and who writes out the guarantee. Some will and most wont.

Its easy to make a .375, .416 Rem or Ruger to, feed in a Mauser or mod. 70...

My 458 Winchester chambered Ruger M 77 Mk ll SS feeds slicker than an Interior Alaskan highway in a January thaw. FOR ME !! A couple friends of mine can get it to hang up on them just by trying to chamber a round. The Spruce King just don't like them . !!!
The 416 Taylor feeds GREAT. In a crf Ruger action with no messing around with anything. Same as my 458.
These from what started life as a 338 Winchester. Speaking of which, the 338 Winchester in a crf Ruger is perhaps the most effortless ly chambering cart/rifle action that I have ever pushed a bolt on . Aweful lot of good to be said about that. At least once you get used to it so your not opening the bolt to see if a round chambered.
I do think that a 410/375 HandH would be a good feeder as all my 375s were great feeder. Jmho.

Pretty impressed with the feeding smoothness and power in my .375 Ruger. Seems the .416 Ruger would fill the bill. Or maybe rebarrel a standard Win 70 mag to the .416 Ruger; a stainless of course. Then there are the Stainless Classics in .416 Rem, but having the long magnum action crf, I would still go for the Ruger ctg.

No belt... so stacks in the magazine more evenly. Shorter body, a bit; so More versatile for bullet seating. Still get the full 3 or 4 in the magazine.

Sako TRGs is also a great action to build on or rebarrel.

Lots of potential. Make your own Romance & Nostalgia...

Can never go wrong with a model 70 stainless classic.

quote:

Originally posted by aklester:
Pretty impressed with the feeding smoothness and power in my .375 Ruger. Seems the .416 Ruger would fill the bill. Or maybe rebarrel a standard Win 70 mag to the .416 Ruger; a stainless of course. Then there are the Stainless Classics in .416 Rem, but having the long magnum action crf, I would still go for the Ruger ctg.

No belt... so stacks in the magazine more evenly. Shorter body, a bit; so More versatile for bullet seating. Still get the full 3 or 4 in the magazine.

My thoughts exactly! I imagine an Echols Legend in 416 Ruger would be the Bee's Knees! However, except for the longer bolt travel, I bet the same rifle in 416 Rem would feed just as well.

quote:

Not necessarily.

Yes, absolutely and mathematically "Mauser Co-sine Law" NECESSARILY.I have the one-piece bottom metal that Duane Wiebe makes for the 500 Jeffery.I used it on the 500 Bateleur (.510/338 Lapua Magnum-Improved-2.7" case length).It is too narrow for that case head, let alone the even bigger 500 Jeffery case head.But it is made to work, and does work well enough, but don't ever expect it to be as slick as if the 404 Jeffery case head were being used.

I have Duane Wiebe 4MJ bottom metals on my two FN commercial M98 actions that easily accommodate 3-down cartridges of my 338 Lapua derivative wildcat cartridges.
The unimproved .423 caliber box has sufficient crush space for the 4th cartridge to be easily picked up under the extractor.
The improved .500 caliber has sufficient crush space for the 4th cartridge to be picked up under the extractor with a bit of thumb work on my part. Some day I'll likely add a Pocket or Rigby style floorplate to eliminate the extra thumb work required to pick up the 4th cartridge.

We are not talking about mere depth of magazine and capacity in number of cartridges here.It is about the ability to pack three cartridges into the box, stacked with stagger,so the center-lines of the cartridges pass through the apex points of an equilateral triangle, all equidistant from each other.

Ron,

I readily admit that I've not physically "Mauser Cosined" the magazines in my two Wiebe 4MJ bottommetals.
I will try to recollect to do so between Friday morning (PDST) and Sunday evening to conduct the test.
- The test being to pull the box of dummy rounds (used for the build feeding work of both rifles), tape or rubber band three cartridges together in a proper "Mauser Cosine", and test whether the magazine maintains the cartridges in the proper "Mauser Cosine" stack or whether its some its only a "non-Mauser Cosine" staggered stack.
- I'll take photos regardless and post results.

A few things to consider in the meantime...
The typical M98 Mauser one piece bottommetal has a straight vertical sided magazines with the interior magazine walls profiled for the cartridge being used to facilitate feeding.

Your Wiebe' 6MX is drop box depth/style bottommetal, the magazine sides are manufactured vertical top to bottom, the interior magazine walls profiled for the 500 Jeffery cartridge, and the magazine will hold three cartridges plus sufficient room to thumb a 4th cartridge down so that the rim is picked up under the extractor when closing the bolt, Replacing your standard floorplate with a Wiebe Coffin (Rigby) Style floorplate will give you a 4th round down plus a 5th in the barrel.

My Wiebe 4MJ is a standard depth/style bottommetal, the magazine sides are manufactured trapezoid shaped top to bottom (narrower at top and wider at the bottom), interior magazine walls profiled for the 404 Jeffery cartridge, and the magazine is designed to hold four cartridges plus sufficient room to thumb a 5th cartridge down so that the rim is picked up under the extractor when closing the bolt. The current 4MJ bottommetal is delivered with pocket style floorplate providing extra magazine space to facilitate the thumb feeding of the 5th round.

I understand from my gunsmith that the unmodified 4MJ bottommetal held three 423/338 Lapua Magnum cartridges (unimproved case) better than the four 404 Jeffery cartridges. The magazine does have sufficient space to easily thumb a 4th round down in the magazine and have the cartridge ride up under the extractor when closing the bolt.
Note: I truly do not recollect if my gunsmith re-profiled the internal magazine walls to better follow the 423/338 Lapua Magnum cartridge profile or not. My gunsmith is retired, he's moved and I have no phone number for him...so I'll have to check my notes both handwritten and notes on a slave drive (very likely will not happen this weekend) to determine if I did make note of this...

The Wiebe 4MJ bottommetal on my 500/338 Lapua Magnum still maintains the trapezoid shaped magazine walls but the internal walls are re-profiled to accommodate the improved cartridge (larger shoulder diameter, straighter case, and for the .500 caliber bullet and larger diameter neck) profile. The magazine still easily holds three cartridges down but there is barely sufficient space in the magazine to thumb the 4th round down so the case head is picked up under the extractor when closing the bolt.

How is this for reliable feeding:

-https://m.youtube.com/watch?v=sAr7d3acMYo-

Since we're not supposed to post direct links, I put dashes on the end, so you'll have to copy and past to your browser.

From a practical standpoint, it really just doesn't get any better than that, fellas! That kind of feeding can be accomplished with several different rounds in a few different actions. Maybe a beltless or shorter round can be made to feed nominally better, but I doubt most humans could discern the difference. A more complete test might show slow quite feeding, feeding with rifle pointed up and down, with the action upside down and sideways. However, folks who've used a properly built Mauser, model 70, CZ 550 etc., extensively will tell you that, if the geometry and feed work is done right, you're not going to have any problems.

Well,
I guess D'Arcy gets a flat-nose feed job right every now and then, especially if you are buying the rifle he built from scratch.

Jim,
You are not going to do anything except to illustrate the tricks used to get cartridges to feed in actions too small for them.
But that is a very interesting subject.


There is more than one way to skin a wildcat.
Riflecrank Incurable Permanente

Ron,

Likely so but now I'm to interested to stop...