These were built at Quantico. With signed gun books.
The thing that grabs my attention is that all three barrels appear to be different lengths. What is the real length from the recoil lug supposed to be 25"?
The thing that grabs my attention is that all three barrels appear to be different lengths. What is the real length from the recoil lug supposed to be 25"?
Total is length is 25". Its 24" from the lug.
I guess the rifles are not standing at the same height. Simply.
Looking for a take off stock does anyone know any body or place thats selling one
You could be right on that. I believe I would prefer the crown on the two rifles on the right.
Get in touch with latinaincovina and twomanattack, both are members here. I know they had either return, or new stock for sale. Posted in the ads section but I cant find it..
Left is a M40A3. Right are both M40A1.
Left is a M40A3. Right are both M40A1.[/QUOTE said:
TwoManAttack, you'd make alot of hide members happy here if you could get ahold of a set of calipers. Most calipers also have a depth measuring capability. A depth measurement, and a ID and/or outer lip thickness measurement would be perfect.
Mr. Senich in "The One-Round War" quotes an MTU spec during the developmental stages of the M40A1. It may or may not be what was settled on for use by the 2112s at the time, but it sure looks like what you have there. That spec was .100" deep to .700" diameter. That would leave a little under a 1/8" lip. If either of your crowns is a little on the large size, two dimes stacked are about .706" in diameter and .107" thick, right about flush with a .100" deep cut crown, if they'll fit.
Are the recessed portions on your two M40A1 crowns flat, or do they have a slight inward taper?
Mr. Senich in "The One-Round War" quotes an MTU spec during the developmental stages of the M40A1. It may or may not be what was settled on for use by the 2112s at the time, but it sure looks like what you have there. That spec was .100" deep to .700" diameter. That would leave a little under a 1/8" lip. If either of your crowns is a little on the large size, two dimes stacked are about .706" in diameter and .107" thick, right about flush with a .100" deep cut crown, if they'll fit.
Are the recessed portions on your two M40A1 crowns flat, or do they have a slight inward taper?
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But every time I see that photo I can't help thinking that the bore seems deeper than the depth at the rim looks. I swear. Some other photos I've seen of real M40A1s that show the crown also seem to indicate a slight dish rather than being flat, if only by the lighting/shadowing. But phographs being what they are, looks can be deceiving. I just wish someone familiar with the real deal could settle this. Forgive me if we figured this out here before- I looked, but the thread is long.
Redfield 1 pc, square corner base on Ebay for $19.95 buy it now. Listed as Remington 722...seller Tangmooa.
Not mine or anyone I know, just a FYI
Not mine or anyone I know, just a FYI
THIS has been discussed in depth. page 8-15 ish...The pic of rifle above, the owner had several pics to choose from and chose that one, EVERYONE said his crown was wrong cause it didn't match GAP's rifles etc etc. Specs I also believe are posted.
not that a refresher aint what we all need! ha.
Regards,
DT
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Both types are correct. Mine was built by Leo Conring USMC PWS 2112 Armorer who built M40A1's at Quantico with Eric Reid. Here's a picture. TWOMANATTACK has some fine examples also all throughout the thread.
I know both types were used. However, I was only issued rifles with the square cut crown. Seems like the style GA Precision more popular was at the end of the USMCs M40A1 tenure and at the begining of the M40A3 inception.
Thankyou for your patience, TwoManAttack. I remember going over this before, so I spent alot of time going way back and rereading to jog my memory regarding any specifics that had been given. This thread is getting really long, some of it due to redundant questions and such.... like mine for instance. I'm taking better notes now though, since I'm planning on having a build started in the next few months.
I found where you had said that the Celtic Rifles crown was .075" deep, and another place where you recalled crowns you were seeing in the Fleet as being "square cut maybe 10-15 deg if any,..." So, it sounds like some, at least, did have a slight dish to them.
So, I have a question for rlm8541 now...
For clarification, do you recall if the angle cut you were noticing was the angle of the cut from the outer rim down to the recessed surface, as opposed to a straight down cut (or straight in, depending on how you look at it), or were you discussing the recessed surface itself being angled slightly (like dished) as opposed to being flat straight across the bore?
I found where you had said that the Celtic Rifles crown was .075" deep, and another place where you recalled crowns you were seeing in the Fleet as being "square cut maybe 10-15 deg if any,..." So, it sounds like some, at least, did have a slight dish to them.
So, I have a question for rlm8541 now...
For clarification, do you recall if the angle cut you were noticing was the angle of the cut from the outer rim down to the recessed surface, as opposed to a straight down cut (or straight in, depending on how you look at it), or were you discussing the recessed surface itself being angled slightly (like dished) as opposed to being flat straight across the bore?
Hey M40_A1....The angle cut that I was referring to seeing is the one that seems to be stiring some question about when it was first seen on an A1. Which is the one that you see now as the standard on the A3/A5 barrels. Similar to the one just above here in post #1213.
I was issued one with this similar cut when I went through the basic course in the early 90's. I remember posting the question to my Cadre about why they were different and they could give no definitive answer at the time. I cant remember seeing any others after. Although, I also really dont remember paying much more attention to it there after. Most all I do remember seeing, much like TWOMAN, was the 90' degree cut crown like in post #1209. Also, from what I remember is that it was completely flat from the 90' cut to the actual bore. No cupping. If there was, it wasn't noticeable to the human eye. Hope that helps.
Kind of off topic, something i kinda wanna throw out there. The A1 was a pretty amazing if not one of the most amazing small arms our Marine Corp ever developed,...moa.
The unique thing about it is the fact that there have been these small nuances that have changed over duration of it's history. Ie....stock cammo patterns, bolt/ bolt shroud replacement, early scope base and scope configuration and barrel manufacture and crowning...etc,etc,etc.
I hate seeing guys getting all worked up over what is right and what is wrong when it comes to attempting to duplicate A1.
As we all know the majority of all the A1's from it's inception up through the time it was taken out of service were built on Vietnam Era M700's (M40's) receivers.
Soooo, with that being said as long as you are using the same parts that were used to build the A1 (or obviously repro parts for most). The combination you decide to use is completely up to the preference of the person having it built. Because, the likely hood of an A1 in the late 90's to mid 2000's being rebuilt and re barreled several time is highly likely. So the A1's that TWOMAN had contact with with the angled crown in the late 90's more than likely had been or possibly been rebuilt several times over its life span with possibly the 90'degree cut crown on it's previous barrel.
So, enjoy your builds and keep an open mind when researching and building. Because ser#221XXX (for example) might have been built at a certain standard when it was first originally built, might have been rebuilt to a slightly different standard several times by the time it was finally retired! Just food for thought...Cheers!
I was issued one with this similar cut when I went through the basic course in the early 90's. I remember posting the question to my Cadre about why they were different and they could give no definitive answer at the time. I cant remember seeing any others after. Although, I also really dont remember paying much more attention to it there after. Most all I do remember seeing, much like TWOMAN, was the 90' degree cut crown like in post #1209. Also, from what I remember is that it was completely flat from the 90' cut to the actual bore. No cupping. If there was, it wasn't noticeable to the human eye. Hope that helps.
Kind of off topic, something i kinda wanna throw out there. The A1 was a pretty amazing if not one of the most amazing small arms our Marine Corp ever developed,...moa.
The unique thing about it is the fact that there have been these small nuances that have changed over duration of it's history. Ie....stock cammo patterns, bolt/ bolt shroud replacement, early scope base and scope configuration and barrel manufacture and crowning...etc,etc,etc.
I hate seeing guys getting all worked up over what is right and what is wrong when it comes to attempting to duplicate A1.
As we all know the majority of all the A1's from it's inception up through the time it was taken out of service were built on Vietnam Era M700's (M40's) receivers.
Soooo, with that being said as long as you are using the same parts that were used to build the A1 (or obviously repro parts for most). The combination you decide to use is completely up to the preference of the person having it built. Because, the likely hood of an A1 in the late 90's to mid 2000's being rebuilt and re barreled several time is highly likely. So the A1's that TWOMAN had contact with with the angled crown in the late 90's more than likely had been or possibly been rebuilt several times over its life span with possibly the 90'degree cut crown on it's previous barrel.
So, enjoy your builds and keep an open mind when researching and building. Because ser#221XXX (for example) might have been built at a certain standard when it was first originally built, might have been rebuilt to a slightly different standard several times by the time it was finally retired! Just food for thought...Cheers!
Hey M40_A1...I guess with all that gibberish I just wrote, the bottom line that i was trying to get at...lol, is because of all of the slight changes that took place over the years, regardless of the crown you decide to go with. You won't be wrong ether way.
Nice stick, and first post, Dr. Swift. Being a build by an independent and relatively unknown? builder, it might be difficult to place a value on it, especially with just 50 rounds through the tube- makes one wonder why it's being sold. I would say MAYBE 2.5-3k IF it shoots. The ad says the barrel is stainless, then states it is chrome moly. Stainless would be the correct choice for the M40A1. Chrome moly would lower the value, IMHO.
I hear you. Take these crowns, just the depth alone. I've heard .050" from Quantico, I believe McMillan speced it as .055", then there were .070" and .090" mentioned several times, and .075" as per TwoManAttack. We all wish there were specific, original examples we could duplicate of all the various crowns actually used, but except for some obscure example out there somewhere, I'm sure all those barrels with their variations of crowns from 15+ years ago are gone, gone, gone, never to be measured for posterity. In a way, it's a good thing there was no one dimentional standard, in another way it can drive one crazy!
Onward...As has been stated elsewhere, there is a noticeable difference between the rings gaps of original Unertl rings and the USO rings. I don't know why USO made their rings a bit short, but they are, and the screws show through the gaps. Are you still making dimensionally correct repros of the Unertl mounts, TwoManAttack?
Absolutely helps, immensely. Thankyou. As my "E" prefixed receiver is from 1995, either of those crowns would work just fine.
I hear you. Take these crowns, just the depth alone. I've heard .050" from Quantico, I believe McMillan speced it as .055", then there were .070" and .090" mentioned several times, and .075" as per TwoManAttack. We all wish there were specific, original examples we could duplicate of all the various crowns actually used, but except for some obscure example out there somewhere, I'm sure all those barrels with their variations of crowns from 15+ years ago are gone, gone, gone, never to be measured for posterity. In a way, it's a good thing there was no one dimentional standard, in another way it can drive one crazy!
Onward...As has been stated elsewhere, there is a noticeable difference between the rings gaps of original Unertl rings and the USO rings. I don't know why USO made their rings a bit short, but they are, and the screws show through the gaps. Are you still making dimensionally correct repros of the Unertl mounts, TwoManAttack?
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Thank you so much for the help, definitely confirmed that the deal was not worth it on my end. Offered him a lower value car for the rifle, we'll see if he bites.
I agree with M40_A1 on his pricing guess, but would bump it up an additional $500 if the stock is an actual return stock with the McMillan certificate of authenticity and you pull the action to verify the markings on the barrel channel. While there were many A1 stocks that never saw fleet service, instead sat in the Albany, GA warehouse in case of WWIII, that one looks rather pristine to be a return stock. And no, those stocks were NOT used in Vietnam regardless what the hell he says.
This is just my opinion. I didn't recognize the builder for one. I didn't see any of the parts marked with SN#'s at all. The stock looks like a "new" Mcmillan M40A1-HTG, if it does not have the documentation as a return stock that's a big hit on price. The barrel crown looks a little rough to me in the 4th picture. The trigger guard shows some sign of rust in the 6th picture. It appears to have the long bolt shroud and standard Remington 700 safety. It's a good looking gun don't get me wrong, however I would not offer up a car for trade. I'd offer about $2100 for the rifle as is. It throws up a red flag to me with the 50 shot round count and the "stainless" barrel and chrome moly barrel reference in the next sentence. If your gonna drop a lot of coin for a M40A1 I'd make sure it's legit.
Just my opinion....Tickle
Here are the actual specs from the USMC on the M40A1
I have been following the M40A1 forum for some time now. I thought the forum members would like the spec from the horses mouth so to say. Here are the actual specs from the USMC on the M40A1 to clear up any questions. Many years ago in the early/Mid 80's Gale McMillan with Bill Atkinson and Tom Sr. of H-S Precision ( Bill was still involved for a short time after he sold Atkinson Gun Company to H-S) build my M40A1. My rifle is featured in Death from Afar : The History of USMC Sniping Vol. IV by Norman A. Chandler.
I hope this clears up any questions.
Enjoy !
IM
I have been following the M40A1 forum for some time now. I thought the forum members would like the spec from the horses mouth so to say. Here are the actual specs from the USMC on the M40A1 to clear up any questions. Many years ago in the early/Mid 80's Gale McMillan with Bill Atkinson and Tom Sr. of H-S Precision ( Bill was still involved for a short time after he sold Atkinson Gun Company to H-S) build my M40A1. My rifle is featured in Death from Afar : The History of USMC Sniping Vol. IV by Norman A. Chandler.
I hope this clears up any questions.
Enjoy !
IM
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Outstanding! That's quite a contribution to this thread. Thank you, Sir. I always have admired your rig in that book, and have to confess a little jealousy, too, in someone having one of those scopes so early. It seems maybe John Unertl was also in on your build? Welcome to the forum!
Yes, John was a part of this build as you correctly point out.. The 10X sniper on my rifle is exactly the same scope that the USMC use on the M40’s. The only difference was the markings. USMC Sniper vs. 10X Sniper. The USMC marked Unertl scope was not available to anyone but the USMC period. If someone had one marked USMC they have that scope under very questionable circumstances. The 10X sniper was only sold to government agencies like FBI ect. From what John told me I had the only one in civilian hands at that point in time. To say the least there are VERY few in civilian hands to date.
For the first time and until recently the DCM had a few that were offered for sale to the general public. I think that the DCM received scopes that needed to be reworked to make then 100% functional. At one point John wanted to buy my scope back from me since the demand was so high and they were so limited in production. John passed away and his wife Elsie was running the company which became more than she could or wanted to handle. At a point in time she sold the company. The new company modified the scope and in my view should of kept it as John designed it. The 10X Sniper / USMC Sniper scopes are as relevant today as they were when they were first introduced. With the challenges in front of 21st Century Technology the new company who purchased Unertl and the high cost to produce the 10X Sniper / USMC Sniper scopes gave an open door to Schmidt & Bender and Leupold & Stevens to jump in. Which they both did. I don’t think that there is a better or more rugged scope built. I would say to anyone who wants one, aim high and get one if you can.
For the first time and until recently the DCM had a few that were offered for sale to the general public. I think that the DCM received scopes that needed to be reworked to make then 100% functional. At one point John wanted to buy my scope back from me since the demand was so high and they were so limited in production. John passed away and his wife Elsie was running the company which became more than she could or wanted to handle. At a point in time she sold the company. The new company modified the scope and in my view should of kept it as John designed it. The 10X Sniper / USMC Sniper scopes are as relevant today as they were when they were first introduced. With the challenges in front of 21st Century Technology the new company who purchased Unertl and the high cost to produce the 10X Sniper / USMC Sniper scopes gave an open door to Schmidt & Bender and Leupold & Stevens to jump in. Which they both did. I don’t think that there is a better or more rugged scope built. I would say to anyone who wants one, aim high and get one if you can.
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Not too many even know about those B-series scopes. I need to clarify that my jealousy (not really the word I'm looking for) was in someone being able to buy one new in the box like that directly from Unertl, who was well known as NEVER willing to sell one to a private citizen. You were very fortunate, indeed. You must have had some pull!
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You bet! I have seen the scopes sell for well over 10K. Remember in 1984 1K for a scope was big bucks. The scope is built like a tank.. its almost indestructible..The Schmidt & Bender nor Leupold & Stevens scopes are built like this scope, granted both Schmidt & Bender and Leupold & Stevens are really great scopes but they are not like the Unertl.
Can any of you answer a basic question for me? Where at on the stock would it be numbered?
Looks like paint pen or marker. That's all they did? I figured it would be stamped. Thanks though.
Typically a sharpie. On the crowns... While it was WAAAAAYYYYY before my day, understand that these barrels were all cut by hand, by different folks. There will be a little variation in length as well as the crown.
Marines use the black el-marko for everything!
This applies to so many in this thread...
The business of selling one's car for an M40 got me thinking, I love mustangs and other classic cars, but if I had a fully restored orginal parts 67 mustang fastback 390 or even a 68 mustang California special, and someone was selling a perfect clone M40a1 with unertl and correct mount, and either 6dig action or preffered "C" prefix, yes I would happily trade either those mustangs for the m40a1! Yeh I guess I'm sick but I don't care!
PS: A 68 Roadrunner 440, that might be a tougher call, its possible I might still trade it for an M40a1....maybe.
PS: A 68 Roadrunner 440, that might be a tougher call, its possible I might still trade it for an M40a1....maybe.
A couple gratuitous shots for the thread. TBA M40A1 and a US Optics MST100 (A1 version) at the range this morning. I tried to get a shot through the optic just for giggles, I think it turned out OK. That's a plate at 300yds.
Obviously the Harris and the stock pattern aren't spec but I still love shooting this rifle. Our range only goes out to 600yds for HP matches but it's still fun ringing the steel. My M24 was a solid shooter but it couldn't hold a match to this rig!
Forgive a foolish question or if maybe I mis-read. The molded stock pattern I thought was spec for some issue rifles being built/rebuilt with new molded camo stocks replacing some smear stocks? I know the smears still lasted a good while(dang fine stock) so maybe not too many molded-camo stocks were used but I figured they still count as "spec." If and when I do an A1 build my plan was to go specifically for a molded-camo stock with C prefix action-unless the molded camo stocks were never used than I'd search out a smear pattern one, but I like the look of the molded pattern.
You must have misread, because I don't see where "molded" was mentioned in his post. The "smear" pattern was "molded" in, and so was the later "blotch" pattern, or whatever you want to call it, but they were both "molded". The photo is too dark for me to make out why the poster said his stock pattern was incorrect, so I can't comment on what's wrong with it. What you DON'T want is any texture. If you don't specify, you could end up with molded-in texturing, which the M40A1 did not have.
I guess what he meant by 'stock pattern not spec' is that his stock is the newer 'forest camo', and issued stocks were 'woodland camo'? Slightly different.
Forest has always been correct, whether smear or blotch. I don't know where the woodland came from. There may have been some woodland stocks for the early 1990s "C" actions, but I have only seen forest on unpainted blotch pattern stocks so far in my research.
BTW, Redmanss, I've been trying to put a "like" on your "All you care about" post, but this page is so picture heavy it never seems to download enough for me to get the buttons to do so (slow connection/computer). That's funny as heck! (and just about true
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Thanks for clarification on the fact that both are molded patterns. I will refer the later as blotch pattern vs smear pattern from now on.
It looks like in the photo that its a smooth finish stock with no epoxy txtr so that's correct. The buttpad maybe isn't spec if most or all had the thinner natural brown pad as std. Or is that electrical tape wrapped around the butt that looks like a thicker black pad. Hard to really tell what's not spec but great rifle nonetheless. I see no problem with using a Harris bipod either although I personally don't like them; this thread or another people have mentioned either temporarly swapping out Witchita front swivel for QD stud for using Harris bipods or using another method if Witchita swivel is permanant. IMO the harris bipod doens't make the rifle less spec as its just added kit personal pref. As long as the rest of the kit is issue than the total is still speck in my book. And I'm not one to feel the need to accumulate the total issue kit for a rifle build, at least not initially but maybe overtime.
It looks like in the photo that its a smooth finish stock with no epoxy txtr so that's correct. The buttpad maybe isn't spec if most or all had the thinner natural brown pad as std. Or is that electrical tape wrapped around the butt that looks like a thicker black pad. Hard to really tell what's not spec but great rifle nonetheless. I see no problem with using a Harris bipod either although I personally don't like them; this thread or another people have mentioned either temporarly swapping out Witchita front swivel for QD stud for using Harris bipods or using another method if Witchita swivel is permanant. IMO the harris bipod doens't make the rifle less spec as its just added kit personal pref. As long as the rest of the kit is issue than the total is still speck in my book. And I'm not one to feel the need to accumulate the total issue kit for a rifle build, at least not initially but maybe overtime.
Been a while since I have posted in this thread. So here are the most recent bases and rings assembled. They just need finishing. If you bought a base TELL YOUR BUILDER THAT EACH ONE NEEDS TO BE HAND FIT TO YOUR CLIP SLOT! Turns out people dont know that the USMC did that to EVERY SINGLE ONE OF THEM! At the least, the rear lug will need to be taken down a bit. Your quality informed builders will know this. Some may not realize it.
Been a while since I have posted in this thread. So here are the most recent bases and rings assembled. They just need finishing. If you bought a base TELL YOUR BUILDER THAT EACH ONE NEEDS TO BE HAND FIT TO YOUR CLIP SLOT! Turns out people dont know that the USMC did that to EVERY SINGLE ONE OF THEM! At the least, the rear lug will need to be taken down a bit. Your quality informed builders will know this. Some may not realize it.
Those look good Two Man, nice touch on the spot weld.
Those unertl bases are looking sexy!
Damn I can't afford to do an A1 build right now but I might have to think about getting a base set and picking up a stock now, even if I can't do a build at the moment. It'll definately be a while before I can afford an MST.
Damn I can't afford to do an A1 build right now but I might have to think about getting a base set and picking up a stock now, even if I can't do a build at the moment. It'll definately be a while before I can afford an MST.
Oustanding work indeed TMA!
Same thing here... I decided to go the Redfield way. Of course, its not a green Redfield, nor a 'smear' stock. But its a great shooter
You've shown me that one before, but that pic's even nicer!(drool)
I always thought highly of the older Redfield fitted A1s as well! Just screams oldschool!
I always thought highly of the older Redfield fitted A1s as well! Just screams oldschool!
A little bit on the Unertl scopes....
From what I understand, the mil-dot reticle was first used in the Unertl USMC/10X Sniper scopes. It was specifically designed for the Marine Corps. Now everyone and his cousins are using mil-dot reticles of one form or another, a testimony to the genius and success of the system.
The first Unertls had windage knobs capable of dialing 4 1/2 MOA either way, and round mil-dots of .15 mil diameter each. The first impression is, "Why only 4 1/2 minutes windage? Isn't that very limiting?" Not with the mil-dot reticle, it isn't. Each dot's spacing on the cross hair represents approximately 3 1/2 MOA, so if you want to dial more than a 4 1/2 MOA wind, you would simply hold on a dot (at 3.5, 7, 10.5, or 14 MOA) and dial the remainder. For example, if you need to compensate 13.5 MOA for wind (as often happens at 1000 yard ranges), you could hold the center of target at three dots over (10.5 MOA), and dial on an additional 3 MOA. For some, though, it's easier and better to just hold for wind altogether, and not dial at all. In that case you don't have a precise aiming point, but you also don't have to keep track of what you have dialed. Later on, some of the scopes were fitted with 8 1/2 MOA winadge knobs, nearly twice the dialing range, but really unnecessary with a mil-dot reticle.
In the beginning, so I've been told, some of the old, original .15 mil dots were being knocked loose from the cross hairs, so some of the reticles were replaced with football-shaped dots that adhered better to the wire. I believe those reticles were made by Premier Reticles. It was said the end of the football shape was easier to "see" than the edge of the round dots for better precision while ranging, but I don't buy that. Personally, I think it was just a workaround of the adhesion problem.
Later reticles featured larger, .2 mil round dots. So much for the football "dots". .2 mils makes sense as the dots were larger and easier to see, and it was easier for the eye to visualize .1 and .2 mils while ranging by using the dots as reference. In other words, the edge of the dot represented .1 mils (from the center of the dot). Half of an additional, imaginary dot would represent .2 mils (again, from center of a dot), and the space of a whole (imaginary) dot would represent .3 mils from the center of a dot. .5 mils is self-explanatory, as the mid-point between dots. Etc. So, .2 mil sized dots were a very good idea for ranging.
Now, some complained that the scope should have had 1/4 MOA adjustments, and the rebuttal was that 1/2 MOA was fine for man-sized targets out to 1000 yards. But, I wonder if the scopes really were not originally, indeed designed with a 1/4 MOA adjustment feature. "What?! Where? What are you talking about?" Well, remember those .15 mil dots that gave way to the football "dots" that gave way to the handy .2 mil dots? It dawned on me the other day that .15 mil is darned near .5 MOA. Holding to the edge of a .15 mil dot (i.e. .5 MOA dot) would have given you that 1/4 MOA increment! Voila! I wonder if that was the reason Unertl went with that size of dot. Maybe it's a .5 MOA dot, instead of .15 mil like I always thought it was. While not exactly convenient to use, any 1/4 MOA POA could be had using a combination of the edge of a dot and the knob. I've never heard of this being taught in the schools as a feature to get 1/4 MOA adjustments, and I've never seen it in any manuals. Maybe it was never taught because it can be a bit complicated to use, and really NOT necessary for man-sized targets. But, I still have to wonder if John Unertl didn't intentionally design it that way in the beginning. I wish he were still around to ask.
From what I understand, the mil-dot reticle was first used in the Unertl USMC/10X Sniper scopes. It was specifically designed for the Marine Corps. Now everyone and his cousins are using mil-dot reticles of one form or another, a testimony to the genius and success of the system.
The first Unertls had windage knobs capable of dialing 4 1/2 MOA either way, and round mil-dots of .15 mil diameter each. The first impression is, "Why only 4 1/2 minutes windage? Isn't that very limiting?" Not with the mil-dot reticle, it isn't. Each dot's spacing on the cross hair represents approximately 3 1/2 MOA, so if you want to dial more than a 4 1/2 MOA wind, you would simply hold on a dot (at 3.5, 7, 10.5, or 14 MOA) and dial the remainder. For example, if you need to compensate 13.5 MOA for wind (as often happens at 1000 yard ranges), you could hold the center of target at three dots over (10.5 MOA), and dial on an additional 3 MOA. For some, though, it's easier and better to just hold for wind altogether, and not dial at all. In that case you don't have a precise aiming point, but you also don't have to keep track of what you have dialed. Later on, some of the scopes were fitted with 8 1/2 MOA winadge knobs, nearly twice the dialing range, but really unnecessary with a mil-dot reticle.
In the beginning, so I've been told, some of the old, original .15 mil dots were being knocked loose from the cross hairs, so some of the reticles were replaced with football-shaped dots that adhered better to the wire. I believe those reticles were made by Premier Reticles. It was said the end of the football shape was easier to "see" than the edge of the round dots for better precision while ranging, but I don't buy that. Personally, I think it was just a workaround of the adhesion problem.
Later reticles featured larger, .2 mil round dots. So much for the football "dots". .2 mils makes sense as the dots were larger and easier to see, and it was easier for the eye to visualize .1 and .2 mils while ranging by using the dots as reference. In other words, the edge of the dot represented .1 mils (from the center of the dot). Half of an additional, imaginary dot would represent .2 mils (again, from center of a dot), and the space of a whole (imaginary) dot would represent .3 mils from the center of a dot. .5 mils is self-explanatory, as the mid-point between dots. Etc. So, .2 mil sized dots were a very good idea for ranging.
Now, some complained that the scope should have had 1/4 MOA adjustments, and the rebuttal was that 1/2 MOA was fine for man-sized targets out to 1000 yards. But, I wonder if the scopes really were not originally, indeed designed with a 1/4 MOA adjustment feature. "What?! Where? What are you talking about?" Well, remember those .15 mil dots that gave way to the football "dots" that gave way to the handy .2 mil dots? It dawned on me the other day that .15 mil is darned near .5 MOA. Holding to the edge of a .15 mil dot (i.e. .5 MOA dot) would have given you that 1/4 MOA increment! Voila! I wonder if that was the reason Unertl went with that size of dot. Maybe it's a .5 MOA dot, instead of .15 mil like I always thought it was. While not exactly convenient to use, any 1/4 MOA POA could be had using a combination of the edge of a dot and the knob. I've never heard of this being taught in the schools as a feature to get 1/4 MOA adjustments, and I've never seen it in any manuals. Maybe it was never taught because it can be a bit complicated to use, and really NOT necessary for man-sized targets. But, I still have to wonder if John Unertl didn't intentionally design it that way in the beginning. I wish he were still around to ask.
The more I think about using the dot (the old size) to get a 1/4 MOA increment, the more I think it is impractical for ranges past 300 yards or so. A one mph change in cross wind at 500 yards would already require about a full 1/2 MOA windage change. And, by the time the dial and hold corrections are calculated in order to use the edge of a dot for a 1/4 MOA increment, the wind would likely change by at least that much. So, possible to apply? Yes. But, hardly practical.
OTOH, at close range, knowing that holding to the edge of a dot would give 1/4 MOA precision might be handy, if not for the fact that parallax at close range would negate such precision. That is, unless the scope's parallax is set for close range, which would then negate the long range benefits of the scope's design.
I don't think the original dot size was pulled out of a hat. I just found it interestingly coincidental that it was .5 MOA in size. Thanks for bearing with my thinking out loud.
OTOH, at close range, knowing that holding to the edge of a dot would give 1/4 MOA precision might be handy, if not for the fact that parallax at close range would negate such precision. That is, unless the scope's parallax is set for close range, which would then negate the long range benefits of the scope's design.
I don't think the original dot size was pulled out of a hat. I just found it interestingly coincidental that it was .5 MOA in size. Thanks for bearing with my thinking out loud.
The USMC hand fit all of the M40A1 Unertl mounts to the actions clip slot. The rear lug was taken down to fit the rifles action. On the mounts we build, it is the same way. They are oversized to accommodate for hand fitting.
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