04-27-2009, 04:41 AM
Join Date: Dec 2002
Location: Springfield, South Carolina
I have had several Mod 94s over the years and primers backing out seemed to come with the territory but you CAN DO SOMETHING ABOUT IT. You simply headspace your cartridges to fit the rifle by not full length sizing the cases. Leave about 1/8" gap between bottom of die and shell holder.
By only neck sizing the cases you don't allow it to fire again with the built in slop in the chamber. Use a minimum published load for this and perhaps cast bullets to save on expense. As the shoulder length goes forward the case will back up towards the bolt face thus supporting the head and the primers will back out less and less. Might take three or four shots if you have a jumbo chamber but eventually the primers will look normal.
There is another method that if done with CAUTION will produce same results in one shot and that is to seat your bullets about .025" over max case length and load single shot. DO NOT LOAD IN MAG TUBE, THEY WON'T FEED.
Loaded "long" will allow the bullet nose to find the rifling and thus hold the loaded case snug against the bolt face when it is fired. Back off your load and use the minimum published load to allow for the possibility of increased pressures. Also only size your case necks maybe 1/8" down the neck, and the bullet is free to adjust itself as the action comes into battery. If you size the entire neck, bullet is held too tight and forces bullet into rifling which could raise pressures to a dangerous level. All you want to do is hold the case head against the bolt face when fired and just a little bit of neck tension is needed to do this. With light neck tension the bullet will slide down inside neck as bolt locks thus you are not jamming bullet in throat.
Once you see your fired primers looking like they are supposed to, start running your die down to say 1/16" gap and using a magnifying glass look at neck/shoulder area to see where the die stops sizing then very carefully adjust die 1/8th turn and size again and adjust until the die just touches the shoulder.
The trick is to only size the case to where the shoulder is just moved (set back)maybe .001" to .002" when bolt goes into battery (locked) position. Thusly you have changed the headspace of the case and made the case fit the chamber rather than the chamber fit the case.
The case is now technically headspacing on the shoulder rather than the rim and min sizing will enhance your case life tremendously.
I wouldn't worry with trying to change headpace on rifle because this is going to get expensive fast on a lever gun and will require a new barrel. A bolt gun headspace can be adjusted by unscrewing barrel, taking off one thread, moving shoulder forward about .020" less than you cut back of barrel off and rechamber on a GO gage.
The Mod 94 was never intended as a high round life platform where the Mod 70 Winchester is estimated to be able to shoot out 50 barrels and still be serviceable.
If it were me I would most likely sell the rifle as a collector and get a Marlin 336. I dumped all my 94s 30 years ago because of this problem.
Even better get a Mod 70 30-06 (assuming you want to stay with brand name) and don't look back. You can still find 30.06 ammo about anywhere, least ways in SC 30.06 is available. You can load it down to 30-30 velocity if you like and even use your 30-30 bullets in it for reloading.
The other day I found a 30 cal can full of 30-30 brass I forgot I had. I FL sized it all and tumble cleaned it and packed it back in the can. Might just try and find a Marlin 336 just to have something to shoot. A 30-30 will only get you to the lower end of the 30.06 range where with a 30.06 you can start with 30-30 energy levels and go way up with a vast selection of bullets available where you are very limited with 30-30 loads.
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