Anvil 087: Sharps Borchardt .45/120

[Applause] any weapon whose reloading die doesn't fit in the palm of your hand is rather epic this is a sharps bore shark not in 45 70 but in 45 120 look at that monster 535 grain slugs of just get out of here we got to put a front sight on this job so we're going to talk about doing some dovetail work drilling a couple of holes in the back of this getting some sights on this thing see if we can hit what we're aiming at before an epic cloud of smoke clouds our way carbon-based life form down the rabbit hole let's go the original rare sight that came on the gun had a round bottom and what we've done is milled this out octagonal so that the rear will actually sit on the barrel here barrel location we'll talk later about centers of mass i'm going to tell you it's probably got to go right here you can't get a rear sight too close to your eyes you just don't want to do it you won't be able to focus on it so this front sight is going to sit out on the end of the barrel out about here somewhere and we're going to go ahead and mill a dovetail in this barrel and i'm going to get down on the towel and show you that and these open sights will probably get used most of the time with the gun this reproduction malcolm site while nice doesn't have even close to the vertical uh adjustment necessary to go beyond about 200 yards with this gun you just don't have enough turret because these things fly like rainbows so ordinarily for long range work the uh the rear scope will be just removed let's see here if i can pop this off the scope will come off the bases will remain in place and then if he really wants to get out there and touch somebody we'll be able to pop that rear we'll be able to pop that rear up like this the background's awful busy for this i'm looking in the monitor here you go the rear is going to sit right there like that and we'll leave enough room that we can get everything in and out um and based on where this is going to go let me show you something there are two things that go into where we're going to put this rear sight on the barrel we've just screwed it in one of which is the balance point when you hang the gun it's going to hang right here so you want the sight not where your hand is grabbing the barrel so the sight's going to have to go forward in my hand or behind my hand the other is the human eye can't focus on something that's only that far away from it so if you want to stand a prayer of looking over these sites it's going to have to go in the forward position i've selected a front sight that is low enough that we can actually have the muzzle elevated you can see here the center of that aperture i don't have a post in it is about the height of the of the rear sight set at 100 yards what we're going to have to probably make some modifications to the front sight to get this thing on at 100 but once we get it zero to 100 we'll be able to scale up and go on out so you cut a dovetail in two steps let's let's draw this dovetail here this piece has got a bottom on it like that and then it has a ledge and then let's just for the sake of argument draw something that looks like a front side ours doesn't look like that but we're going to do that you got to know the distance from here to here and you need to know this distance and this included angle right here all right um let's see we're going to call that an angle you'll just do that right okay so in this particular case this site has a 60 degree angle on it let me get it up here where you can see it 60 degree angle i've got a dovetail cutter that exactly mimics it but cutting dovetails isn't quite that straightforward you don't just take a dovetail cutter and blow all this you take a a straight mill and you mill out the hole and then you come in with the dovetail cutter here let me move this out of the way i got to get up a little bit i'm a bit off camera here there we go and then you come in with the dovetail cutter and you remove the corners like this so it's a two-step process to drill in this hole and you can't move the bottom of the hole so there's some games you play on the milling machine you touch off on the top surface of the barrel right here i'm going to touch off right there and then when we fly back in with the cutter will fly in we'll take take the bottom of the milling cutter of the dovetail cutter we'll touch the top of this and it will come down the distance that we need to come down and cut the bottom off it clear is mod um not my best drawing set ever but let's go uh let's go cut us a dovetail because i'll tell you one thing's for sure we got to put this site as close to the front end of the gun as we can physically get it and still have it look correct just so that we're clear this dovetail is 380 it's a hundredth out down and the wall of the barrel is 250 thou the bore is down here around my hand somewhere so we're good this 250 thousandths of an inch number is going to come in handy when we do a couple of things one we know we're not going to cut the dovetail through the through the bore and don't laugh because it has happened and it hasn't happened to me but boy i've had i haven't had to learn that lesson but when we go to drill the screws to mount the rear sight when we go to drill that screw right there we i know that i can comfortably come in about 180 thousandths of an inch and i know that because i've already done that math um when i mounted the scope the dovetail cutter and uh hang on a minute those of us that are blind he's 359 thousands so i know that there's about 20 slop front to back off the dovetail cutter um and then that number right there tells me that once i'm done making the cut i can then start milking backwards about 20 thousandths of an inch and moving one of the walls until this just starts in and then this thing is larger on one side than it is on the other by a thousandth or two so it'll draw up when it goes in so you can sit there and measure this all you want but at the end of the day you just have to cut it by feel at least that's that's my opinion and i'm sticking to it okay so i've set the wheel to zero and i had brought down the cutter until it was just singing on the top so now every time i got the handle out of the way on the knee here so what i'm doing is i'm making passes by and i'm taking about a ten thousands cut every time so here we go on our first cut and the chips are starting to fly and then we'll go back through and we'll pull the knee up there tenth out come back the other way and we're gonna do this until we plunged in a hundred thousandths of an inch and we'll have a rectangular cut okay we're gonna move it one more time and now bruno is gonna do his thing we're gonna blast through this [Laughter] okay so we'll back it away turn the quill off and switch over to the dovetail cutter so we bring the cutter down and bring the barrel back underneath it and i'm just using the quill and i'm bringing it down until i feel the cutter just touch off that's all the more precise it's got to be right there lock the quill and then back the knee away here we go the knees coming away now so after setting zero on the knee i'm dropping the knee here and then we'll get this thing out of the way come back over to zero there's zero and i don't think i moved it back far enough there i went away a little bit further okay we'll back it up all right so once i set zero on the knee i drop it down to 100 thou and then i get that handle out of the way because i don't want to bump into it move it we'll fire the spindle up when you commit to cutting this dovetail you're committed you can't sneak up on this like we did cutting the groove you just got to come in and the optical illusions are amazing here that's why you see me walking around the side and i'm doing the idiot check is this cutter in the right spot once it's in the right spot you just got to commit and make the chips fly and it's one pass straight through a little bit of oil on this one and here we go chips are flying now we're going very very slow the edges of this dovetail cutter are extremely fragile you gotta handle this thing like it's a rotating egg this is a classic example right here including pigs how to fly he usually doesn't work and typically results in a pissed off pig nice and easy guys nice and easy don't rush this plenty of oil plenty of chip clearance you'll see me come back out here and blow on a little bit with some air this is to make sure that a chip doesn't follow the tooth and then it just oh it makes a bloody mess up here and we're through so the next thing we've got to do is pull that 20 to 25 thousandths of an inch forward in this particular case i've zeroed out the position indicator here and now i'm going to move the wrong axis of the table and bring the cutter forward in five thousandths of an inch increments we're making the dovetail wider now and from here on out it's a cut-and-try kind of deal and i know i've been uh beat up for that but trust me the difference between this thing fitting beautifully and being sloppy is about two thousandths of an inch so milk your way in milk your way in and take it over to the bench and finish it up with a five um all right all i got to do now is pop a couple of holes in this thing let's get over to the device um and tap one of the site base holes and we'll go from there bruno spent all of this time lining this shot up but i want to show you this so now we have the front sight mounted dovetail is cut i didn't delve really really deeply into doing this because this is something you just got to make a bunch of mistakes at and learn how to do and again a custom 45 120 borshard is not the gun you learn on so we'll go right here all right i had sharpie marker down this area right here um just so that i could see the prick punch marks the barrel wall thickness is 250 thou up at the front so it's even thicker here so i came in 180 on the mill and i drilled down these holes 180 and i knew i wasn't going to punch into the barrel so a little trick i'm going to show you here i have two different taps and these taps are both let me get my finger out of the way one of these taps is it's not a starting cap you don't have enough room in a blind hole to do a starting tab but you can do a finishing tab if you're very careful and you're extremely mindful of the amount of torque you're putting on this thing and it'll run and but when it bottoms in a hole it will stop moving and if you push it you will snap the tap off in the hole and then you are dually and truly hosed because these taps are a lot harder than this steel green mountain made this barrel and i'm going to tell you what i've had nothing but luck with those guys i'm not sponsored i'm not paid to say that but i'm going to tell you every green mountain tube i've ever put on a gun has run like a scalded cat this gun has been fired already i'm going to tell you that we shot it once just to verify the headspace um we will shoot it many many more times then i transition over to a tap that i've cut the bottom off of and i'm going to see if i can't bruno pull the focus up please i'm going to show you that i've cut the bottom off that tap and that thing cuts threads almost to the very bottom you can't start a hole with this however what you can do is finish a hole with this and i'm going to show you where the torque starts winding up on this once we get it running here hang on a minute let me find the threads where are we here there we are right there it'll grab them and this will go down and then it will start pulling torque right there and there it's cutting so i'm getting i got almost a full turn out of that thing more down on the bottom but then it comes up tight and it's tight in case you haven't noticed i've been driving this tap branch with my fingertips i'm not killing it but this is an 840 screw that we're going to use to hold this in with that is an 836 tap well you're using the wrong tap for the hole no i'm not the interference between a 36 and a 40 it will begin to interfere with itself out about seven eight nine turns in we're only going to go down about three or four turns but as the 36 threads start interfering with the 40 screw it the thing will drag up come up tight and hang on in a way that lock tight will not hang it up don't use it on through drilled holes but in this particular case it's something i do and i'm sure i'm going to take a lot of guff for that but that's what i do there that's how these are tapped that's how everything else is tapped so let's get this out of here and i will tell you that i have not made the special funky screw for the front yet because this was set up for number um six screws and i've got number eights in it this is an 840 here for the front let me get that going here this eight begins to tighten up right about here so when we come because of the interference between the thread pitches and we tighten down on that that is good and tight so let's hang the optics on this pig and take a look at what we got here's the scope and the scope slides up and it slides backwards onto these mounts they slide back and then they're captured with a screw over here on this side captured the screw over here on this side if you come back give me a little wider angle i'll show you the whole system on this thing here we go so here we have this has external turrets on it and these mounts are exactly the right distance apart that every number on the top of this gives you a quarter of an moa so one complete turn on this is supposed to be an inch now these tubes these tube sites were set up for slightly higher velocity rounds this thing is like a mack truck and it's dropping like a rainbow so i don't know how this scope is gonna perform on this weapon but i'm gonna tell you what tell me that's not totally bad ass weapons this big are good for hunting elk buffalo house tell your wife you're going house hunting she might believe you for a change uh i don't know the proof of the puddin's in the eating so i guess sooner or later there's going to come a time when we're going to have to shoot this [Applause] thing yeah that will remind you who's boss anybody else want to try at it here's the front sight that brought us all here we cut that dovetail used the lowest front we could get in order to get it down on top of the gun it has inserts this is alignment number 17 in its lowest iteration they make this in a variety of heights re-pop this is not one of those scopes that's designed to move it does have exterior turrets and then we took the rear sight and went ahead and milled the octagon on it so when it sat on the barrel there you can see the octagon sits down we used number eight screws instead of number sixes throughout this and here's how this thing is designed to work the optics on the gun are designed to just slide off and come free and then you have the rear sight available with its original elevation now this site's calibrated in for 45 70 bullet weights and i don't know where that's going to leave us there's a little bit of range time left for this oh boy i'm gonna have to go find a younger shoulder well here's the business end of this cannon right here as the breeches drop down you can see the um ejector pops open there there's an empty just slide that thing all the way up in there and the breech comes up and locks it shut now when you close the gun here there's a safety down at the bottom that has to be pulled backwards in order for it to work so the safety pops on every time you open up the breech in order to ensure that as you're closing this breach you don't just accidentally stroke the trigger and have one hell of an uh an unintended consequence 535 grains of get the heck out of here you gotta be kidding me that's a pretty heavy projectile for anything it has the trajectory of a rainbow that's the finish round right there and that thing is enormous look at that everything's bigger than some of the cigars i smoke one of our one of our listeners here sent me a comment in patreon and said his uh his gunsmith that he was apprenticing under said this is the gun that you fire get back up on your feet reload and fire again the gun itself the bluing on the receiver is original we've blew the barrel i haven't made friends with the scope yet there's still a lot of work left to be done on this thing but man i'll tell you what i have really enjoyed this as always it's been a pleasure guys we'll catch you on a flip side with something else [Music] [Music] [Applause] um brian that was some amazing machining work you did for me man i cannot thank you enough

Channel: Mark Novak

Views: 180,447

Rating: 4.9544969 out of 5

Keywords: #anvilgunsmithing, @anvilgunsmithing, Mark Novak, Anvil, Gunsmithing

Id: HrwVgfgEpkE

Length: 22min 25sec (1345 seconds)

Published: Thu Sep 10 2020