IAB Business Rifle is Low Left

[tangsight]

Greetings again from Corpus Christi. I took a model 66 Sharps business rifle replica (IAB) to the range over the weekend, with a box of ammo I had made that shoots well in other BPCR's. I shot at 50 yards at a big target because I did not know where the thing was going to put the boolit. I had one inch groups (two minutes of angle), but they were a foot low and a foot left. The sights on the gun are basic Lyman type post front and notch rear, and are centered in the dovetails. Barrel length is 28 inches, sight radius is 22 1/2 inches. The rifle has no visible defect.

The amount of correction required makes me think the barrel is flawed (bent or drilled off center or something). How do I find out? Can a gunsmith attach some sort of device that will expose that sort of flaw? And, assuming I find the flaw and I need a new barrel, where to obtain it?

[Buckshot]

................Octagon barrel I take it? You sould be able to look at the muzzle and see that much of an offset, if the bore is off axis. Or just use your dial calipers checking 12, 3, 6, & 9 o'clock positions at the muzzle to check for an off axis bore. It could be (I'd doubt it) that the barrel might be slightly bent? Check with a yardstick.

Did you try boresighting it? That might give you the best idea as to what's up with it. I don't know who the importer is for IAB, although I know that EMF used to sell them and might still. But for a barrel (unless you're looking for one under warrenty) quite a few barrel makers offer 45 cal octagon barrels. Of course you'd need ot find a gunsmith to put it on.

..............Buckshot

[NickSS]

What buckshot said is correct but there could be another thing to check. I bought a Spencer recently and it shot a foot low at 100 yards with 40 gr of FFG powder and a 370 gr bullet. The same gun shot a foot high with smokeless loads of 20 gr of 5744. It may be that the sights you have on your rifle are not the proper hight for your load. About 20 years ago I had an IAB rifle like yours and it took me almost no time to determine that the factory sights were worthless. I replaced them with a Lyman 17 front sight and a mid range tang sight. They the rifle shot just fine for the several years I had it until I graduated to a Shiloh Sharps rifle.

[1874Sharps]

Tangsight,

What was the load you were shooting? It is good to see there is at least one more shooter of the old stuff in Corpus! Do you shoot at CCPRC? I do not think I have seen you there, but maybe I have.

[montana_charlie]

A foot of elevation and a foot of windage at 50 yards...that's a lot to correct for.
I suppose you have examined the muzzle crown, and checked for cleaning rod wear in that area...?

CM

[RMulhern]

tangsight

I hate to say this brother but ......I just don't have much faith in some of these so-called 'makers' of Sharps rifles! Shiloh Rifles in Big Timber, Montana makes the best and next to that I'd opt for C. Sharps in Big Timber.

All I could tell you is take a file to the front sight and a brass punch and drift that rascal over!

[tangsight]

Thanks to everyone for the info. This forum is always the best. FPMIII, I'm thinking I may have to drift that rascal right out of the dovetail. Montana Charlie, the muzzle has a slight bevel to it very shallow, and I can't see any dings or dents. That was a good steer, though, I had not thought of looking there. 1874Sharps, yes I shoot at CCPRC. I'll be there early this coming Saturday, if you want to hook up. The load is 62 grains volume FFg Goex, sifted for fines, then thrown from a 55BP measure into Remington brass. Lyman 457125 with SPG lube in the grooves. Thin vegetable wad over the powder column to protect the base of the projectile. Brass is belled to allow a slip fit, powder is compressed enough to allow all grease grooves to be covered. CCI magnum primers. Light rifle; this load bucks pretty hard. NickSS, yeh I'm pretty sure part of the elevation problem is too tall a front post and not using a tang mounted rear. I have some cowboy action factory 45-70; I'll see how and where they group next. Buckshot: the yardstick says the outside is straight; the mike says the hole at the muzzle is equidistant from all the flats. My boresighting method is less precise: 2" ShootNC stuck on the kitchen wall, eyeballed from twenty feet across the room. With the bull in the center of the bore, the sights are looking at the bull, halfway out from center, in the one o'clock quadrant. Near as I can tell, ennyho.

[jlchucker]

When you move a front sight, it doesn't take very much movement to change bullet impact quite a bit--noticeably less than when you move the rear sight. Between moving front and rear sights in opposite directions, you may actually have plenty of dovetail left at each end to get to where you want to be. Go easy on the front for starters though. A couple of whacks at a time. Once you get the windage where you want it, you can then deal with the elevation problem.

[KCSO]

Well here's the bad news... I fix a lot of these guns and IAB is the absolute worst Sharps repliica made. The actions are not particulary well hardened, the chambers are not well cut and the barrels, as you have found are not straight. Everytime someone around here buys an IAB I know I will have lots of work to do. If you are that far off at 50 yards either the barrel is crooked or there is a defect in the bore.

[montana_charlie]

If you are that far off at 50 yards either the barrel is crooked or there is a defect in the bore.
Let's all pray it ain't so...

Occasionally, you will see a post by some guy who has an IAB Sharps that shoots straight. While (more often than not) he will describe some amount of fixin' required in the lock, it seems that some IAB Sharps barrels are better than some Uberti Hiwall barrels.

Given a choice between a Pedersoli and an IAB, I wouldn't even consider the latter. But, I actually enjoy hearing about guys who get them to shoot well.

Also...keep in mind...the opening post said the rifle stayed within two minutes, right out of the box, and with no load development.

CM

[tangsight]

Thanks to everyone. I'm headed to the local range early tomorrow morning with a brass hammer, a drift pin, some cowboy action 45-70's, and the box of my own loads I've already shot with. I'll report back Sunday.

[Buckshot]

................I'm one of those guys gifted with a truely superb IAB Sharps. Did it have a problem? Yes it did, and that was the chamber. My gunsmith called it a 'Lawyer Chamber'. I asked him to run a 45-90 reamer into it and ever since it has been a doll of a shooter. Never had a moment's fault with the set triggers or lock. The barrel gleams internally. Guess I just got the right set of parts put together :-)

................Buckshot

[SharpsShooter]

Buckshot,

The one I had years ago many years ago was horrible. It did not last 100 rounds before the lock failed due to soft parts. The barrel had chatter marks the entire lengrth that I spent many hours lapping to improve it only slightly. I'd never touch another now. The planets must have aligned that day yours was assembled.

SS

[montana_charlie]

................I'm one of those guys gifted with a truely superb IAB Sharps. Did it have a problem? Yes it did, and that was the chamber. My gunsmith called it a 'Lawyer Chamber'.
"Lawyer Chamber"
Meaning it was substantially deeper than 2.1 inches???
CM

[tangsight]

Lawyer chambers and product loyalties aside, I promised a report on my trip to the range Saturday morning and here it is: Set up in the mud as the sun came up. Fired three riunds to get a centerpoint from which to calculate an adjustment. Had to move the front and rear sights in combination a total of .1125", more than could be done on the front sight only. After a drift pin and mallet session, two more singles were loosed, wherein I expected, and got, strike point movement to an inch beyond 6:00, so the windage is corrected. I opted out of shooting the smokeless ammunition I had said I would try, because I felt these results were consistent enough without that data.

Elevation is another calculation away. The rear sight is a Lyman hunting sight, with elevation adjustment available by raising or lowering a back plate which is then secured by two small screws. Total available elevation correction is about .1", which is eight inches at 50 yards. With the back plate at its highest setting, I am nine inches low at 50 yards. With the back plate at its lowest setting, I am 17" low at 50 yards. I can get most if not all of that out of the front sight by filing off two tenths of an inch, but a tang mounted windage adjustable rear sight seems easier. Does my method seem sound? Comments, anyone?

Incidentally, all of these shots fell within an inch at fifty yards, so at this point it's no worse than a two minute of angle rifle. I'd be shooting my Pedersoli Sharps were it not for a frozen rear adjustment trigger screw. Anybody got an Easy Out?

[montana_charlie]

I'd be shooting my Pedersoli Sharps were it not for a frozen rear adjustment trigger screw. Anybody got an Easy Out?
Are you talking about the small screw behind the rear trigger...the one that is flush with (or below) the surface of the trigger plate?

Quoting from the Pedersoli manual, "For some set triggers there is a side screw (# 5) to make sure that the screw (# 1) doesn’t loosen. This however does not happen too often and only to guns that have very strong recoil."

Not content to leave anything un-examined, I decided to re-adjust Screw #1 to see how much effect it had on operation of my DST. Since the cautionary note said "some set triggers" I made the assumption that mine did not fall in that unusual(?) group that has a Screw#5 (which is only visible with the DST removed from the wood).
Being in possession of many good screwdrivers, I totally destroyed the head of Screw #1.

Upon further consideration, I removed the DST from the stock, and found that mine DOES have that little setscrew...locking Screw#1 firmly in position. You can't imagine how pleased I was to find out that my rifle is so 'special'.

When I ordered (2) replacements for Screw#1, I also bought an extra Screw#5...just in case.

If you have a Pedersoli manual, you should read it.
If you don't have one, it's located here...
http://www.davide-pedersoli.com/newsEn/Manuals_ManualsEn.pdf

CM

[waksupi]

Being in possession of many good screwdrivers, I totally destroyed the head of Screw #1.

CM

Whassa madda? Doncha own a Dremel?

[tangsight]

Montana Charlie; No, the DST's on my Pedersoli are not equipped with that little set screw (#5). I too have a multitude of screwdrivers, (or rather, HAD; now it is multitude minus one). Screw number one really was impossible to move. Had to drill it out; plan to retap and replace screw #1 with something that has an Allen head (I have a multitude of them as well).

[montana_charlie]

Screw number one really was impossible to move. Had to drill it out; plan to retap and replace screw #1 with something that has an Allen head (I have a multitude of them as well).
Be sure to let us know what kind of luck you have drilling and tapping that trigger plate.

It's supposed to be 'color case hardened'...and I'm curious about how hard it really is.
CM

[tangsight]

Montana Charlie: Success! Drilled the hole in the trigger plate out to 13/64" and tapped it with new threads. Have been able to adjust the triggers (previously the rear screw, which was frozen, and which adjusts spring tension to the rear trigger, was set at a point where the triggers would set, but then the front trigger would not release the hammer. So all I had was a hard pulling front trigger). Now all is well.

Interestingly, the trigger plate was quite easy to drill out and tap, despite the reputation of the color case hardening.

[SharpsShooter]

Tangsight,

Sounds like ya got the bullet heading the right direction. A good soule tang will go a long way to helping your elevation issue without beaking out the files. The real sticker shock is how much you can spend on one. I like MVA but for the price, you might think a rifle is included. Keep after that thing. Hopefully you lucked into one of the good ones.

SS

[montana_charlie]

Interestingly, the trigger plate was quite easy to drill out and tap, despite the reputation of the color case hardening.
Well, just the 'case' of the plate is supposed to be hard. The interior is supposed to be 'normal'.
If the case hardening happened after the factory drilled and tapped that hole, it would have a hardened surface (inside the hole) which might have caused you problems.
It appears that the hole is drilled after the 'case' has been created, so it is all 'machineable metal'.

Thanks for the report.

CM

[Red River Rick]

The "Case" portion of the manufacturers claims are then BS. If the part was actually "Case" hardened, you would have never been able to drill out the existing threads.

So, with what you accomplished, which is a good thing, only proves that the term "Color Case Hardenening" doesn't apply. The only true part to the term is "Color", no hardening what so ever.

RRR

[montana_charlie]

If the part was actually "Case" hardened, you would have never been able to drill out the existing threads.
Uhh...Rick,
Case hardening only affects the surface of the part...right?
The interior remains as 'soft' as the steel was originally...right?

Since .050" is considered a very 'deep case', don't you agree that it's possible to work case hardened steel if you first anneal, or grind through, the thin case?
CM

[NickSS]

sounds like you have a good barrel as a light barreled 45-70 with the load you are shooting will do well to hold a 2MOA group. All you need is a good rear sight. Unless you like open sights I would suggest you get a tang sight with windage adjustment for your rifle. Zeroing it should be easy after that.