M40A1 repo mounts and rings

[Frank Green]

So I did pm three guys that they're mounts shipped but I'll put it here so guys know the stuff is moving....

@RIGREG

@AndyK

@kft101

As I get more updates I'll message you guys.

Don't everyone else beat me up... LOL! I'm still waiting for mine and for two mounts I have to deliver personally to ret. USMC SS guys. When I get they're mounts will be having lunch together. They're only a 1.5 hour away from me.

Later, Frank

 

[Frank Green]

So I pm'd a couple more guys that they're mounts are shipping today.

I did talk to George at GAP as he got his mounts on Friday and he measured them etc... and said they are awesome!

 

[Frank Green]

Small oh boy…..

Guys please check your mounts when you receive them. Look on the top flat between the rings. If you get a mount that’s stamped 7393. That mount was suppose to be mine. It’s the last 4 digits of my rifles s/n.

I didn’t ask for it be done… they did it as a thank you for putting this all together and I didn’t find out till just recently.

My mounts came today along with the others I have to get to local guys/SS guys and no mounts with a s/n.

 

[Frank Green]

Well it’s pretty for sure a thing there was a fubar in shipping!

PLEASE, PLEASE check your mount or mounts when you get them for a stamped s/n. Someone got my mount is what the conclusion is coming to.

Thanks, Frank

 

[AndyK]

Frank,
Mount arrived!!! Really nice - thanks so much...
I checked, no numbered mount in the box.
All the best,
Andy

 

[navynambu]

Hey Frank, I received the mount in the mail today. It's stamped 7393.

 

[Frank Green]

Hey Frank, I received the mount in the mail today. It's stamped 7393.

Ok... how can I get it from you? I'll send you one of the extra's that I got. Ship it up to me and let me know what I owe ya for it.

I'll send you out another one tomorrow and I'll throw some $ in the box to cover the shipping from you to me on mine.

 

[navynambu]

Ok... how can I get it from you? I'll send you one of the extra's that I got. Ship it up to me and let me know what I owe ya for it.

I'll send you out another one tomorrow and I'll throw some $ in the box to cover the shipping from you to me on mine.

I'll send it back to you on the address on your box, thanks.

 

[Frank Green]

I'll send it back to you on the address on your box, thanks.

Thanks! I'll pm you tomorrow your tracking number.

 

[tfont48]

Has anybody confirmed compatibility of these mounts with the badger ordnance m40a1 Simrad cap? I ask cause the two other mounts I’ve tested were not (TMA and ICE)

 

[Frank Green]

Has anybody confirmed compatibility of these mounts with the badger ordnance m40a1 Simrad cap? I ask cause the two other mounts I’ve tested were not (TMA and ICE)

The hole spacing is different on the BO caps. So those are suppose to be to the original spec. The ICE mounts I know for sure they don't line up. I've got one. So I bought a BO cap and modified it.

The mounts that were made that I helped do the buy on are suppose to be to the original spec for the hole spacing. I didn't double check that as of yet because the BO cap I have I modified it. I did put it on the new mounts that we all got... and the holes didn't line up on the modified BO cap so I will take a stab and say yes they are to the old spec.

A new/repro cap is in the works as well being made by the same place that we did the group buy on.

 

[Frank Green]

So here is a update on the mounts. I took one of the ones I got and fit it to my original 40x action that was clip slotted at the Remington factory custom shop.

I had to take off about .020" from the back side of the rear lug. I put a 45 degree chamfer on the back corners to make sure the back corners so it didn't get tight there/bind with that inside radius of the clip slot on the back of the receiver. The angle was about .050" on each back corner I did.

The mount went on to the receiver with no issues.

It did sit higher because that back tang as to how it's machined. So I did some checking and was involved with a conversation with George at GAP and a few others. The sample mount that the shop had... didn't have the bottom of the rear tang have the radius to match the rear bridge of the Rem. 700 action. I was told that that was intentional to give the mount some built in moa for the scopes to have enough elevation out to a 1k yards. Land even told me that.

If I was going to do the mounts myself... I actually had two versions in mind. One matches what we got which is the same as the Ice mounts but then I did one with the rear tang to match the Remmy rear bridge. I just thought it would look cleaner.

We think the one mount supplied was a really late version where the intentions was to true up the rear receiver bridge and then fit the mount to the receiver. It was jokingly told to me maybe we should call it M40A1.2. Rumor I was told it was Chandlers idea. I can't confirm that myself. Anyways for whatever reason... here is where it's at.

GAP is getting they're mounts reworked so that rear tang will have the radius done to it so it matches the receiver.

I took the mount for my 40x and went on a limb here myself and set it up in the mill and cut that radius on the back bottom of the rear tang to match the Remmy action. Think it's a 1.819" radius.

I like how it looks much better. So the maker that made the mounts... if anyone wants they're mounts rear tang modified to match the rear bridge. Send it in and they will rework it at n/c and return it back to you. If you want yours done... PM me and I'll get you the contact info.

If anyone buys the ICE mounts it won't come with that rear radius either. The first ones didn't have it as well and I got one of them.

Here is some pic's of the mount that I fit up to my 40x. On the edges of the mount the funny looking discoloration is from when I put layout die on it before I machined it to fit.

Later, Frank

 

[tfont48]

Out of curiosity, did you or someone you know shoot the rifle and zero both before and after the modification to the mount you describe above? I am curious how much elevation change this modification induces. My thoughts are it should shift POI up significantly, just not sure how far.

 

[Frank Green]

Out of curiosity, did you or someone you know shoot the rifle and zero both before and after the modification to the mount you describe above? I am curious how much elevation change this modification induces. My thoughts are it should shift POI up significantly, just not sure how far.

No I didn't shoot it.

It's a 40x I picked up on 308w... I just wanted it for the action. I just haven't stripped it yet.

I think the POI up would be quite a bit. I can measure an unmodified one and give you a close guess how much it would be.

 

[tfont48]

No I didn't shoot it.

It's a 40x I picked up on 308w... I just wanted it for the action. I just haven't stripped it yet.

I think the POI up would be quite a bit. I can measure an unmodified one and give you a close guess how much it would be.

That would be greatly appreciated.

 

[Frank Green]

That would be greatly appreciated.

Because the other unmodified mounts won't drop on to the receiver and I took a couple of measurements the best I could.

I would say the flat tang mount will sit up about .030" more than a mount with the radius. it's been a quite a while I made a scope mount from scratch. I've got to dig out my machinist book and do the trig/math work to see how much built in MOA it would give you. I'll try and do it sometime this weekend.

Later, Frank

 

[cplnorton]

Frank, I have a real M40A1 mount. Would it help you in anyway to get any info off it? I do have an actual schematic of the original M40A1 mounts too, but I don't know if it has the measurement on it or not.

This is an original in that spot.

 

[cplnorton]

Here are a couple original M40A1's in Marine inventory. This is how they sit. I would be curious what these look like and how they fit on there without any modification. Because there is a slight Gap in the originals but that is because of the way the underside is cut.

 

[Frank Green]

Here are a couple original M40A1's in Marine inventory. This is how they sit. I would be curious what these look like and how they fit on there without any modification. Because there is a slight Gap in the originals but that is because of the way the underside is cut.

I sent you a pm.

 

[Frank Green]

Out of curiosity, did you or someone you know shoot the rifle and zero both before and after the modification to the mount you describe above? I am curious how much elevation change this modification induces. My thoughts are it should shift POI up significantly, just not sure how far.

So doing the math and if I'm doing it all correctly... the mounts are about 6" long. With a .035" difference from front to back... that would give you right around a 20moa built in elevation.

I've got my mounts at home... but if they are right about 5.5" long... if they would be .032" higher in the back.... that would be right at 20moa. I'm measuring between .030" - .035" without fitting up another base right now.

 

[Mywifesgunakillme]

I received two ICE M40A1 mounts and have to say that I am very pleased with them. The machine work and attention to detail are the best I’ve seen BY FAR. I have an original to compare to… these mounts are just what anyone who has been patiently waiting for to be produced…. Delivered. Couldn’t be happier.

 

[kft101]

So for those interested in the fit of existing or prior production simrad caps for these mounts, I did a fit test with:
A. Repro mount from this group run
B. Original Unertl mount (supposedly according to the person I got this mount from and compared to other real Unertl mounts I have)
C. Badger Ordnance simrad cap
D. TheHogsDen/TwoManAttack simrad cap

So here’s what I found out:
- The original mount and TheHogsDen simrad cap hole spacing are pretty much centered horizontally on the split halves contact faces
- The repro mount from this group buy has its hole spacing non-centered and are located slightly outboard
- The Badger Ordnance simrad cap has its hole spacing non-centered and are located slightly inboard
- Though I did not take calipers to the hole spacing on each hardware, you can visually see the difference in the below photo (the edges of the ring halves do not line up in the photo due to height differences, but they are all basically the same on the inner diameter)

Therefore, and based on fit tests with all different combinations of hardware:
- The original mount and TheHogsDen/TMA simrad cap fit together. This is also confirmed with other original Unertl mounts and TMA simrad caps I have with my existing M40A1 builds
- The repro mount from this group buy will not work with either Badger or TMA simrad cap without modification

The (only) combination mount and simrad cap that will work together without modification:

 

[Frank Green]

There are a run of simrad caps being made for the repo mounts on this group buy. The cap was also loaned from Ed Land that is being used to make them.

The more I find out about the caps and mounts… the more variations that seem to exist. From what I’ve gathered so far… 3 slightly different variations of original mounts is what I’m getting. Best I can come up with.

 

[Frank Green]

Even Marty at Badger warned me... about the caps and mounts and the holes lining up on things that are out there.

 

[kft101]

All things considered, I would think the Unertl mounts would be based on the original Redfield bottom screw rings. So I took out a couple different sets of Redfield 1” bottom screw rings and compared them.

I compared:
1. Original Redfield 1” bottom screw ring
2. Another Redfield 1” bottom screw ring
3. Unertl M40A1 mount ring
4. Ring from this repro mount buy

So one surprising tidbit (to me anyway) is that the original Redfield rings use a larger screw than the Unertl or repro mounts (same size screw used for the simrad caps, obvi). I haven’t measured it, but I’m guessing the Redfield rings use the common 8-40 screw.

Aside from the screw size difference, the rings on the real Unertl mount I have are exactly the same as the Redfield rings, including corners of the bevel lining up and the positioning of the screw holes (basically in the middle of the surface faces). Cannot swap and tighten the ring halves between them due to the screw size differences, but eyeballing the smaller screw Unertl top ring onto the larger holes of the Redfield bottom ring, they do line up.

Tried screwing in the Badger simrad cap onto Redfield bottom ring, but even with the Redfield’s larger screw hole, could not tighten down the second screw due to tension with the non-aligned hole spacing (the Badger simrad cap’s screw holes are a bit inboard vs centered).

But since the HogsDen/TMA simrad cap’s hole spacing are also centered and fits my original Unertl mount, it fit the Redfield rings as well:

 

[Frank Green]

All things considered, I would think the Unertl mounts would be based on the original Redfield bottom screw rings. So I took out a couple different sets of Redfield 1” bottom screw rings and compared them.

I compared:
1. Original Redfield 1” bottom screw ring
2. Another Redfield 1” bottom screw ring
3. Unertl M40A1 mount ring
4. Ring from this repro mount buy

View attachment 8714115

So one surprising tidbit (to me anyway) is that the original Redfield rings use a larger screw than the Unertl or repro mounts (same size screw used for the simrad caps, obvi). I haven’t measured it, but I’m guessing the Redfield rings use the common 8-40 screw.

Aside from the screw size difference, the rings on the real Unertl mount I have are exactly the same as the Redfield rings, including corners of the bevel lining up and the positioning of the screw holes (basically in the middle of the surface faces). Cannot swap and tighten the ring halves between them due to the screw size differences, but eyeballing the smaller screw Unertl top ring onto the larger holes of the Redfield bottom ring, they do line up.

Tried screwing in the Badger simrad cap onto Redfield bottom ring, but even with the Redfield’s larger screw hole, could not tighten down the second screw due to tension with the non-aligned hole spacing (the Badger simrad cap’s screw holes are a bit inboard vs centered).

But since the HogsDen/TMA simrad cap’s hole spacing are also centered and fits my original Unertl mount, it fit the Redfield rings as well:

View attachment 8714133

Yes the Redfield rings are 8-40.

The Badger cap threads are different. I forget what they are. I have it written down at home.

I did what you did....I tried the Badger on a Redfield lower ring. Wouldn't line up. So I took the Badger Simrad cap and redrilled and tapped it to fit the Redfield. You have enough meat to do that. I'm going off of memory but the hole spacing is around .050" difference in total.

 

[tfont48]

It's not the craziest thing to accept that between the reproductions and the originals, that there may be issues with ring caps/simrads being cross compatible. I am however quite curious what mount the badger simrad is supposed to fit? If it doesn't work on an original, then which reproduction were they made for?

Sincerely, someone who just wants to shoot his A1 at night.

 

[Frank Green]

It's not the craziest thing to accept that between the reproductions and the originals, that there may be issues with ring caps/simrads being cross compatible. I am however quite curious what mount the badger simrad is supposed to fit? If it doesn't work on an original, then which reproduction were they made for?

Sincerely, someone who just wants to shoot his A1 at night.

Marty told me the Badger caps are made to the original specs. I do believe what Marty is telling me.

The threads in the Badger caps are 6-32. Again the hole spacing is about .050" overall difference in width vs Redfield rings.

So..... your all guess is as good as mine.

From what I hear the original mounts where run in a couple/few different batches/lots. Are there variances or where changes made over time. I would say that is a definite possibility.

I know in conversations with Marines that worked with the rifles/used the rifles back in the day... I've had three different guys tell me... they never seen one mount that was the same as the next mount. Everyone was different. That's primarily from fitting them to the receiver stand point.

 

[Skunk]

I’ve got a Badger SIMRAD cap that fit my original scope mount just fine….

 

[ToBeVeryFrank]

For those of us that missed this opportunity, where/when should we be looking for more of these mounts to hit the market?

 

[John L]

For those of us that missed this opportunity, where/when should we be looking for more of these mounts to hit the market?

If your referring to the mounts, they can be found at a few places. D&D Gunworks is making them, along with ICE in Australia and his seem to get good reviews. I'm not sure where Frank is getting them done at, and Chad at LRI is working on a repo but not sure when they might be ready to go to market.
If your asking about the SIMRAD caps, I believe Frank will be selling those in the near future.