Gunsmithing Opinion on milling slot in feed ramp for longer OAL in Remington 700 type action.

[radmcg]

I have a Pierce action in 7 SAUM. I want to shoot 180s. Measured the OAL to rifling looks like it is under mag length in accurate mags 300 WSM mag. Called Pierce to ask if it would affect action. The guy I spoke with said it was fine. Remember reading on here people have different opinions (Including Jerry Stiller). Could any of the gunsmiths ( or people that have done it and put lots of rounds through their rifle) on here give me there opinion. Looks like I need a 1/10 inch deep slot to clear max OAL of the magazine. Just when I look in the action it just scares me as this is the thinnest section right where the lower locking lug is.
AHA
Rad

 

[DAVETOOLEY]

The lower action lug is the weakest of the two. The load on the lugs increases over 30% going from a .473" based case to a .550" case. I wouldn't do it.
What's your mag setup?

 

[bohem]

Listen to Dave. I advise against it for 2 reasons:

1) Strength and stiffness of the load path.
2) Feeding, if you ignore #1 you usually need to go back and polish in a secondary feed ramp so that the bullet ogive doesn't dead-end into a wall or scrape along a sharp edge.

I still advise against it due to strength/stiffness concerns with a magnum case.

 

[Sonic Crack]

.1" is a good chunk to cut out. I cut the ramp on my Lawton 8500 in 338 but that was only .030" and Im not worried about that because its a beefy action. you may be better off getting a long action

 

[radmcg]

Thanks guys. I Have been thinking of doing this for a long time. Just wanted to see if anyone had done it with a WSM or SAUM. The set up is an AICS stock with accurate mags. The only reason I was even considering it is the exact same slot is cut in my Surgeon 591. What ticks me off is McFred here on the hide had a supplier that made a Drop mag bottom metal that moved the mag box back in the action like a wyatt BDL mag box does. So the back of the magazine slot could be extended to take the longer round not the front. When I checked the company was not making them anymore. With all the WSMs and RSAUMs especially the new 6.5 seems like someone would come up with this. Has anyone seen a failure of the lower lug on a rifle this was done on? Seems like one of the Magazine companies ( won't mention names) actually recommends doing this modification to accept their magazines on their web site. Just a lot of conflicting opinions out there. Also remember every one talking about the 338 Lapua and the long ultramags in the Remington action and this same issue.
Thanks
Rad

 

[Ring]

to be clear, you talking about adding this notch so the tip of the bullet will clear the feed ramp right?

while both of these pics are pretty bad on how they did them, on mine, all that was needed was a small notch maybe 1/4" wide and 1/8" deep
this can be done with a dremel, and should have no effect on the structural integrity on the receiver

 

[jpretle]

Looks like it would be better to take out the short tit at the back of the magazine well----that little portion that the middle screw goes into. You would have to rebuild the mag box, but that is a better way to go, in my view.

 

[radmcg]

Yeah Ring that is the mod we are talking about. What caliber is your rifle in?
jpretle. That has already been done to this receiver for the wyatt box in the HTG stock it was originally in. The problem is when you change to a DBM set up the magazine does not take advantage of the rear space so the magazine still sits in the same places and if you use moded AI mags or accurate or alpha mags that are opened up to 2.950(?) the bullet tip hangs under the bottom of the receiver ring.

 

[knockemdown]

Yeah Ring that is the mod we are talking about. What caliber is your rifle in?
jpretle. That has already been done to this receiver for the wyatt box in the HTG stock it was originally in. The problem is when you change to a DBM set up the magazine does not take advantage of the rear space so the magazine still sits in the same places and if you use moded AI mags or accurate or alpha mags that are opened up to 2.950(?) the bullet tip hangs under the bottom of the receiver ring.

I did this to my Surgeon 591WSM action , after switching to a DBM, running ALPHA WSM mags.
The newer Surgeon 591 actions have that part of the action slotted, but my original 591 did not.

Took a paper towel and gobbed it up into the chamber, so metal chips wouldn't find their way up inside.
Used the Dremel with a gentle hand to make the same relief cut that the newer Surgeon actions have, dead center in the ramp about 1/8" deep. Same as what Ring's pics showed, just a bit more clean, centered and smooth. Afterward, hit the exposed metal with a Sharpie to 'rustproof' it...

Just go slow, be careful and make sure ya flush the whole action out with brake cleaner to get any metal filings warshed outta there.

 

[Ring]

I did it to a 700 in 260... My buddies GAP 308 has it as well

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[Wheres-Waldo]

A few thousand USMC M40's have it done...

 

[Straight Shooter]

The lower lug abutment is thee very highest stressed location of the two lug action design. It is the first place the lug abutment distorts on high pressure firings I would never cut anything from this spot. I consider any action cut in this manner destroyed.

Just my opinion.

 

[300sniper]

The lower lug abutment is thee very highest stressed location of the two lug action design. It is the first place the lug abutment distorts on high pressure firings I would never cut anything from this spot. I consider any action cut in this manner destroyed.

Just my opinion.

Even this one?

 

[Killswitch Engage]

Shit 300....that fuckers junk. I will take it and use it as a demonstration piece to show how not to destroy an action. You want my address?

 

[cal50]

............should move that pesky threaded hole on the bottom as well for added strength.

 

[Straight Shooter]

The Surgeon is made that way. Big difference liability wise if the factory makes it that way or someone alters it by cutting into it later on.

I know a Remington is pretty thin in this area. If I were to cut on the support that helps hold the bolt in place and it blew up I would be crucified. I just wouldn't do it.

For me, a better solution is a Wyatt box. It takes the cutting to an unstressed area of the action. I feel pretty safe with that mod.

 

[300sniper]

Dimensionally, the Remington and Surgeon are the same in that area. I'd bet money the materials have very similar mechanical properties. The lower lug abutment on both actions will see a similar load.

I'm not going to tell someone to do it, but me personally, I'm not scared. Now if someone can produce pictures of lower lug abutment/feed ramp or upper lug plastic deformation or fractures due to this mod, I'll certainly reconsider.

 

[Sonic Crack]

Dimensionally, the Remington and Surgeon are the same in that area. I'd bet money the materials have very similar mechanical properties. The lower lug abutment on both actions will see a similar load.

I'm not going to tell someone to do it, but me personally, I'm not scared. Now if someone can produce pictures of lower lug abutment/feed ramp or upper lug plastic deformation or fractures due to this mod, I'll certainly reconsider.

I just wacked out my 700 for AW mags, Ill shoot it this summer and have a good inspection on it to see if there is any problems.

 

[pinzmann]

When GAP built my 7mm WSM on a Rem 700 action, this is exactly what they did for clearance. Has about 1200 rounds down the tube.

 

[Straight Shooter]

With regular use I doubt it would ever be a problem. During a mishap it gives a weak link to allow the bolt to move downward releasing the upper lug and allowing the bolt to exit the action towards the shooter. Russian Roulette ala single shot. I don't think I like those odds at all. Not one guy that ever blew up a rifle thought it could happen to them.

 

[300sniper]

With regular use I doubt it would ever be a problem. During a mishap it gives a weak link to allow the bolt to move downward releasing the upper lug and allowing the bolt to exit the action towards the shooter. Russian Roulette ala single shot. I don't think I like those odds at all. Not one guy that ever blew up a rifle thought it could happen to them.

Do you feel the 591 is an unsafe receiver?

 

[Straight Shooter]

Since the 591 comes with that small cut I believe it passed it's stress analysis and is deemed safe by it's maker. The Remington doesn't come with the cut so I'm not so sure. All it takes is a scratch for a stress riser to form a crack. I know you saw the overload Defiance action that broke right through the lug pins holes.

A couple years ago Kirby Allen documented lower lug setback of more than a few thousandths on uncut Lapua based rifles he built that were running hot loads. Enough that he will not use Stainless actions for some calibers.

I'm no engineer but I've looked at stress analysis pictures of the Bat Action that Varmint Al has on his site. At 60,000 psi, just the edges are on the verge of plastic deformation with plenty of meat behind so it doesn't permanently distort. Now if that pressure is doubled or tripled and failure starts to occur I could see where it could let go entirely. This is on a single shot action where both lug abutments are fully supported. A two lug repeater is missing most of it's support on the lower lug. My objection is cutting the center out of that support.

 

[gewehr]

Wyatts box all the way, you won't regret it


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[LawnMM]

Did it and then some on a 308 but that isn't a magnum caliber...

 

[fryj00]

I think we're making a mountain out of a molehill here. Anyone building a gun that uses a long cartridge (like 2.960) in a short action has had to do this mod. Scores of guys across the country have done it (myself included) and I don't recall any stories of anyone junking an action because of it. In fact, I know a lot of enterprising, self-reliant folks with good-shooting rifles. Nuff said.

 

[Ledzep]

I understand for liability purposes why smiths would be leery to do this mod. I've also seen similar cuts made in old Mauser receivers on the top part of the ring to feed .30-06 ammo into rifles designed for shorter 8x57mm ammo. I have some Alpha mags that I was ignorant when I ordered and can't use because rounds nose-dive under the feedramp. I've been tempted to do something about it, but haven't yet. Most likely I'll just buy different magazines because my loads are a 2.800" and I don't need to push OAL.

 

[mcfred]

I think we're making a mountain out of a molehill here.

The OP asked for opinions about this, and I think this thread has been a polite compilation of such.

For me I think it's a bad idea to cut that part of a receiver. That is a piece of high grade steel responsible, in part, for containing several tons of white hot fire a few inches from my face. I'll cut the rear part of the receiver that's holding much less force with much lower consequences if it fails.

Most disasters are a chain of factors that happen to combine in just the wrong way. Personally, I'd like to have as many links there as are easy and reasonable. Like safety glasses. I've never needed them, but I still wear them because it's an easy link to add to the chain. You could probably take 2 lug nuts off of each wheel on your car and have no problems. But I don't think this makes it a good idea, especially when there is no reason to do it. Why not just cut the rear of the receiver? This could be a feature and selling point for a brand of DBM (that moves the mag back to take advantage of longer COL) and would be another product to slightly enhance our hobby. I guess I'm not one for short cuts. $0.02

 

[fryj00]

Honestly, the area that we're talking about cutting is so far behind the part of the receiver that immediately supports the lugs and the barrel tenon that I don't see how you can even consider them related. There is also a huge cutout here for the magazine already and nothing (that I can see) to induce a stress riser.

 

[mcfred]

There is also a huge cutout here for the magazine already...

Yes, and another cut for the feed ramp... this what we are talking about.