Home Forums Hunting & Shooting Hunting Rifles No play in magazine box

A recent discussion brought something to my attention that I've read about before. Specifically, that a too tight magazine box can bind the action and cause inaccuracy in a rifle.

I grabbed my Ruger M77 Mk. II, popped open the floorplate, and checked the magazine. There is no play at all in the magazine box with the floorplate open. Would it be advantageous for me to mill down the magazine box a bit to give it a little play? Could modding the magazine box in this way affect the rifles current performance negatively?

I'm not unhappy with it's current performance, even though it has room for improvement. This rifle isn't the "internet typical" less than MOA all day long (if I do my part) that is so often claimed, but it's current performance is good enough for hunting.

Given factory ammo that it doesn't like it can turn out 2-2.5" groups (5 shots). With factory ammo that it favors it will turn out < 1.5" groups (5 shots). With good handloads it will turn out 1-1.25" groups (5 shots). And with it's few favorite handloads it will turn out groups in the .5's to .8's (mostly 3 shot groups).

Would it be worth my time to mill a bit off the mag box to give it some play or should I just leave well enough alone?

You don't have the forward trigger guard screw gorilla tight, do you? Mine is just barely snug, and not quite that.

If you want to know, pull it apart, remove the box, reassemble and test fire again without the box.

They also tend to like the forward lug screw gorilla tight. Have you bedded it?

I still consider 1" 5 shot groups as just fine, unless you competing in benchrest. The next question to really know, after you pull the box, is to find out what she does at 200, 300 etc.

I had it bedded, floated, and the trigger lightened by a smith a few years back. Honestly, I haven't touched the action screws since he worked on it so I don't know.

I guess the easy answer is pull the box and single feed and see what happens.

Thanks.

Be sure the center screw is just snug and I would float the mag box.

+1

You have a hunting rifle that will put 3 shots with good handloads into less than an inch and you want to monkey with it???? What are you going to accomplish? Maybe it will put 3 shots into 1 hole. Will that gain you anything?
Any of my hunting rifles that will consistently give me the type of accuracy you already enjoy are considered reliable meat getters and done.

It's true, that it's 100% functional as a hunting rifle as-is. But if floating the mag box has the potential to give me gains in any way with little to no risk, why not?

The second reason I'm considering it is consistency / repeatability of it's current accuracy. If the mag box isn't floated and I break down the rifle will I get the same accuracy upon re-assembly? Or will the max box bind causing my sub-MOA groups to start giving flyers? It's much like the argument to bed a rifle that already shoots well. One may wish for consistent, repeatable performance.

But I appreciate your point of view. I knew there would be those that thought I was a numpty for even thinking about tinkering with it.

I'd float it. Just file the cut outs on the bottom of the mag box deeper. There is one on the front and rear. Doesn't take much to float it. If the mag box isn't floating, it in theory could be putting upward pressure in the middle of the action.

Install a bore sighter, loosen and tighten the screws and check the readings before/after.

Not sure if one can remove the mag box on a Ruger, but if so, remove the box and repeat the process.

I just bought a Hawkeye-- see my recent thread.

https://www.24hourcampfire.com/ubbth...4277/The_shaman_s_last_30_06#Post8924277

I relieved about .2" off the bottom of the magazine first thing. Some people remove twice that. It seems to be something you can do that easily removes one factor from the mix.

The other thing I did was go out and get a torque wrench and tighten the front screw to 92 in/ft and the back screw to 60 in/ft. The middle one I just made barely tight.

BTW: One thing it WILL do, accuracy aside, is it will make the assembly of the rifle easier. When I first got the rifle, I put it on a wood stock from the original tupperware. I was worried the wood stock wasn't going to fit. I had a struggle getting itall to go back together. After relieving the bottom of the magazine box, it went back together like a dream.

One other tip. When you reassemble the rifle, put a piece of electrical tape over the catch for the magazine. That way, when you tighten everything down there will be just that much more clearance. It makes it easier to open.

Just to be clear...

Here is the magazine box from one end.


And the other.


Upside down from first end.


Upside down from second end.


And a side view.


Where does the milling need to be performed? Just along the entire bottom edges?

Thanks.

In pictures 3 & 4, I just removed a small amount of material in the bottom of the notches with a file -- deepened the notch, so to speak. If I could do it without screwing up, anyone can.

Ah, I see dogcatcher223 also mentioned the cut-outs on the bottom. For some reason I was thinking the entire bottom edged needed to be filed.

Glad I asked.

Okay, she's fixed. There is now a bit of play in the magazine box with the floor plate open (and with it closed there is no rattle).

Interestingly, the last person to have this action out of the stock was the gunsmith (when he floated and bedded it). The screws were no where near torqued to Rugers specs (According to my Wheeler F.A.T. wrench, which isn't necessarily the most accurate.):
Front action screw was ~40in/lbs
Rear action screw was ~15in/lbs
Middle screw was correct as it was just barely snug.

After replacing the action in the stock I torqued to the following:
Front action screw ~65in/lbs
Rear action screw ~45in/lbs
Middle screw just barely snug (< ~10in/lbs).

When attempting to close the floor plate, it wouldn't latch. After a little trial and error I determined that it was the rear action screw causing the binding.

I backed the rear action screw down to ~40in/lbs and the floor place still wouldn't latch.

I backed the rear action screw down to ~35in/lbs and the floor plate latched, but with a little difficulty.

I backed the rear action screw down to ~30in/lbs and everything worked 100%.

Anyone foresee any issues with these torque settings?

I know that Ruger recommends 95in/lbs of torque with the front action screw, but I don't trust the $30 Harbor Freight torque wrench enough (and the F.A.T Wrench only goes to 65in/lbs). I've read the HF 1/4" torque driver is known to have issues (fails to click when you've reached desired torque settings) and I'd rather live with ~65in/lbs than damage the firearm trying to torque it to spec.

Is this in a wood stock now?

If you've got the floorplate latch moving around when tightened, then you have a bedding problem that can be fixed. I would get everything bedded properly if I were you. There should be no binding when tightened, not even of the floorplate. That means that something somewhere is high-centering.

This is in a factory laminate stock. It was bedded by a local smith who came recommended to me.

It might be time for a skim bed... It happens..

Azar, have you shot it yet?

Azar, torque the front and rear screws down, and leave the middle screw out. Does the floorplate latch then?

If so, that means you had too much torque on the middle screw. Crank the front and rear screws down, and install the middle one just finger tight with blue locktite.

Or remove a little bit of the stock.

admin100,
No. Today was my sons birthday party, so I spent all day doing that. Perhaps I'll get time next weekend.

Dogcatcher223,
It's not the middle screw as I verified that. I had the middle screw backed out (high enough it was proud of the trigger guard) and screwed the rear screw down to 45in/lbs. I then went down in 5in/lb increments until I had 100% reliability and that was at 30in/lbs.

Steelhead,
It's possible it's due to the bedding job. The smith glass bedded around the recoil lug, 2" worth of barrel and the tang. Perhaps just take some of the bedding off the tang area...?

In any case, I feel better about these torque settings then what they were at when I took the action out of the stock. I went from 40/15 to 65/30. But it's still not at Rugers recommended specs. I'll probably shoot it first before relieving any wood or bedding.

Thanks for the feedback.

I would guess the trigger guard and floor plate were not bedded by the local smith?

It sounds like they need to be so that they are level when installed and not "rocking" back/forth (high-centering or just plain un-level) as the action screws are tightened.

There does appear to be a bit of skim bedding under the floor plate around the front action screw, now that you mention it. Nothing around the trigger guard though.

Another option to consider, thanks.

After I had bedded my rifle if I torqued the screws to tight the floor plate would not close properly? My particular Hawkeye shoots fine without the screws torqued to factory recommendations.

Perhaps I've had it wrong in my head for the torque specs on the rear action screw. I remembered I had e-mailed Ruger years ago asking about torque specs.





So both the rear and middle screw should be just "hand-tight" and backed out 1/8" of a turn. No wonder it was binding at 45 in/lbs. Even 30 in/lbs sounds like it's tighter than recommended by Ruger.

Since it seems to function 100% as-is, I'll leave it. If I think it's causing an issue, I'll back it down bit-by-bit.

Thanks for all the help.

For my Rugers

65 in/lbs front
50 in/lbs rear
middle screw barely in the gun


Everything functions and shoots excellent

I guess everyone needs a hobby.....

My rifles but one, including 2 Ruger OM, are all bedded the same. Full length receiver bedding plus 2 or so inches of bbl, magazine well (with clearance all around and is not a bearing between receiver and bottom stuff, which is also bedded. Front and back screw holes are column bedded with epoxy, or I think on the M98, I have a steel pillar in there. All are free-floated from 2 inches or so forward of the receiver - wherever the epoxy bedding ends. Except the Mauser, which wears a heavy barrel bedded out to fore-end. Most anything I'd hunt with in any of the rifles does 3 shot groups into 1.5 at 100, and most of that goes 1.25 or less. Not much goes very much under 1.0, but some does (I've a 250 grain handload for the RU77 .338WM that puts 3 into an inch +/- at 200).

I don't need no stinkin' torque wrench either. Front screw gets snugged down tight as I can by hand, then the back one. Most of these have index marks on the bottom metal just for luck. Middle screws just snugging up and that's it. I have no idea what the torque values are, and seldom have a problem with not coming back to the previous POI without adjustment after disassembly/reassembly.

If you tighten the front screw down as tight as it can go, then the rear one, and either goes from "coming snug" to "tight" in more than a half turn, your stuff isn't bedded flat enough in the stock, or it is warping around the mag box.. A quarter turn is better, and an eigth best of all.

The .260 Rem 725SA is my problem child - er - hobby.... Shoots most any 140 gr to 1.25 or less - mostly a bit less. It shoots everything else I've tried into 3-5 MOA.

Still, 140 grain isn't a bad bullet weight.... I'll play with hand loads (starting with untried 130 gr bullets) once I get back to where components and my reloading equipment is readily available. For some odd reason, airlines won't let one carry bulk powder/primers in luggage.....

.2?

3/16 of an inch is .1875
twice that is .375 (3/8")
maybe you meant .02 ?

Shot the rifle a month ago with floated mag box and new torque settings. With my old accuracy load the rifle went from 1.136" 5-shot group @ 100 yards to 2.179" 5-shot group @ 100 yards.

Oops!

I should have followed the sage advice of only messing with one thing at a time so I knew for certain what caused the issue. Easy enough to go back to previous torque settings though, so I backed the rear action screw back down to 15 in/lbs. I didn't get to shoot it again until last Friday.

The crappy part was I only had three shots left of my accuracy load. 1.067" 3-shot group @ 100 yards. Wish I had a full 5 shots to get a fair comparison. Shots 4&5 could easily make it a 1.8" group as well as having them land within it. Oh well, no way to tell how it would have played out.

All is not lost though. I still have some bullets from that same box (160g Sierra GameKing SBT) and the brass is the same lot as before. The newer lot of powder is ~5% faster than the one from 6 years ago and I went from the Winchester WLR to the Federal 215 mag primer. And of course the aforementioned return to 15 in/lbs (from 30 in/lbs) on the rear action screw.

The results:
5-shot group @ 100 yards: 1.059"
Velocity: 3,007 fps (114 fps gain over old accuracy load)
Extreme Spread: 5 fps (reduced by 40 fps over old accuracy load)
Standard Deviation: 2 fps (reduced by 3 fps over old accuracy load)

Seems I have a new accuracy load.

Guess my rifle doesn't like the rear screw very tight, as per Rugers recommendations.

Now I need to see if my other established loads fell apart.