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Re: Burgess' mag box dimension formula!

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30 June 2004, 07:00
<allen day>
Re: Burgess' mag box dimension formula!
Roger, until someone comes up with a magazine box that is mathematically of the proper dimensions for the new short, fat magnums, these cartridges simply won't feed properly.

That's why masters like Tom Burgess, D'Arcy Echols, and Ted Blackburn build and install boxes that are mathematically-correct. The factories are usually trying to just cut corners.......

AD
30 June 2004, 09:04
KevinNY
Scrollcutter,

Agreed, they could put more effort into ALL their rifles feeding properly. I guess the bottom line is they just don't check each one and if they did they would cost more.

I like my 300 WSM and it has served me well at home and in RSA but if I had it to do all over again I think I would just buy a used Supergrade in 300 Win. Mag. for my travels just for ammo availability.
30 June 2004, 08:20
Scrollcutter
I'm not saying the WSM family sucks. I know better, but they (Winchester) could have put more effort into the boxes.

Mine feeds, as well. However, with the cartridges all splayed out due to the box being too tight, I would hardly call the feeding perfect.
30 June 2004, 08:24
Chuck Nelson
You know, I have to smile abit at those who talk about feeding. I have fed cartridges into rifles who's owners thought fed like greased pickles, but they sure didn't.



I once went into a sporting goods store early one morning and talked the guy behind the counter into letting me feed a bunch of WSM's. Guns came off the shelf and into the warehouse we went. I can't remember how many we checked, but not a single one of them fed properly, and friends who own SM rifles have had the same problems.



Your short mags might feed well, but then again they might not.



Chuck
30 June 2004, 06:05
Scrollcutter
Here it is from the horses mouth.

The dimensions below are taken from my own M70 chambered for the dreaded 270 WSM. No wonder people are having feed problems.

Apply the formula to your own rifle (doesn't matter what the make is). See if yours is off dimension. Take a minute to post your own dims.

Quote:

Take the diameter at about .200" forward of the base, or at the belt, Multiply this times 1.866025 ( sine of 60 plus one) and write it down, next slide an adjustable parallel at that point in the magazine box and measure the mag box width inside. Worst case scenario measure with a mike outside and subtract the wall thickness of the box times 2. The formula resultant is the theoretical yellow line down the middle of the pavement, so you subtract the interior from the theoretical. Next you measure at the point of the shoulder on the case and run the formula on that number. Here there is a caveat. If you use reloads use the dia. on one that has been full length resized. You subtract whatever the ammount less than theoretical came out of the base end calculation from this number and that is what the dimension should be at the shoulder. The closer a straight cylinder your case measures the more critical the dimensions are for proper feeding. Ie. if the shoulder end was .020 less than ideal then the shoulder end must be less that same ammount also.




Dims for reloaded ammo are:
Shoulder... .5374
Base.......... .5534

Theoretical box dims:
Shoulder.... 1.0028
Base.......... 1.0327

Rough mag box dims:
Shoulder..... .864
Base.......... .957

Differences of:
Shoulder.... .1388
Base.......... .0757

Mine does seem to feed, reluctantly, but the cartridges look very uncomfortable in the box.