I have an old style Ruger M-77 with the tange safety in .243 A.I. it started as a .243 Win. and was rebarrelled with a Shilen #3 S.S. in .243 ACK. IMP.
The problem I have is it will not feed well from the mag. what type of mag. modifications do I need to have done?
Thanks
Randy

Randy,

Depends on what kind of trouble are you having? Unless you have some unprimed dummies, remove the firing pin from the bolt. Load the magazine and work the bolt slowly and see what is happening.

The only problem that I can think of is that the shoulder diameter of the improved, being a bit larger, is being prevented from emerging from the magazine by the feed rail as the bullet starts up the feed ramp and may even cause the bolt to lose contact with, and over ride the case head.

This would require slightly altering the forward portion of the feed rail to allow the shoulder to clear, and allow the case head to slip up under the extractor once the bullet starts up the ramp.

Unless you are very experienced in this type of feed work, which you probably aren't since you are asking this question, seek professional help in resolving this.

Malm

Malm,

You mentioned removing the firing pin to check feeding with live rounds. Do you think this is entirely safe? I've thought about doing it many times, but always chicken out -- logic tells you it can't fire but I'm paranoid about somehow crushing the primer or something, then explaining a hole in the basement wall to my wife. I guess the best thing to do would be get off my lazy butt and make up some dummies to play with, or dump the powder from live ones...

Not questioning, just wondering,
Todd

If you close the bolt and lower the knob you will have to worry, which might happen if your not mindfull of it. I think GM is just giving safe than sorry advice here. If you don't lower the bolt and the firing pin is not protruding, you are safe just feeding out of the mag. The old push feed Rugers extractor may not snap over the head until the handle is lowered though. If you don't push it all the way in I doubt you'll need the extractor anyway. Am I being unsafe, I've never worried about it before?

My brothers dealing with the same thing in a 300WSM that originally was a 243win. I suggest a smith that does lots of conversions, someone with experience.

I am constantly checking feeding in this business and I don't always have dummy ammo on hand. Customers bring me their custom assembled ammo and I have to make sure this stuff feeds reliably. I believe removing the firing pin is the key to doing this safely.

Regards,

Malm

To answer the question that was being asked (sorry for the earlier diversion of your thread):

I had a similar circumstance with Mauser actions, twice.
#1: 7.65x53 action used for a 270 -- the narrow part of the rails was further back than you'd want for a 270 casing, resulting in loss of 1 in mag capacity. It fed ok though.

#2: VZ-24 used for 416 Taylor -- the rails were widened up top, but the feeding shoulder (for lack of a better word) on the underside of the receiver rails was not modified. It still fed ok, but the front of the cartridge tended to pop free and cross the centerline of the action -- especially the one from the left side of mag. Went away after I massaged the rails with a grinding stone, and re-polished. This was not very smart, even though it worked; removing too much would basically have ruined the action.

I am not familiar with the Ruger action -- i.e. whether lips on the mag box control feeding, or the underside of the receiver rails do -- I'd suspect the former, since using the rails for feeding would necessitate tweaking the action for each class of cartridges. You have been given good advice, take it to a good gunsmith.

Good luck,

Todd

Feeding problems were not uncommon with the early77s. In most cases the second cartridge would fail to move up in the rear and the bolt would simply run over it. To correct this could be maddening.
I recall one 338 which would fail every time unless the bolt was operated very smartly. It needed the jolt of the bolt hitting the stop to pop that cartridge into position. Well, after I had fought with the damn thing for about 2 hours, I lost control and launched the mag box across the shop at a pretty fair velocity. When it hit the wall on the far side the spot welds on the back of the box broke. Feeling better, though a little embarassed, I reassembled the rifle and it fed flawlessly!
The next one that came in was a 280 and I felt a lot better about working on it since I figured I had the answer. I broke the weld at the rear of the box and reassembled it. The result? A dismal failure. If anything it was worse than before. I closed the box up a little more than it had been and welded it back together and it worked. So I still don't know the secret. I kind of think the stack angle is wrong and this is what causes the problem but I wouldn't bet the farm on it. Regards, Bill.

the bottom of the receiver does control the feeding and the type of feeding problem is.......... the case will feed about half way in with the tip of the bullet just starting to enter the chamber but the base of the case will not release from the mag. looks like to much material on the feed area on the receiver to let the case come free.
new question. there are no smiths here in my area with a good rep so I'll have to send it to someone. anybody know of a good one that works on Ruger actions

I'm sure you'll get plenty of referals to great smiths that'll guarantee the work from guys here. Sounds pretty simple, though it could be screwed up still if not done right.