Throating out .300" in 45-70 cartidge

[Cottonwood]

Okay here is what I've done.....

I called a gunsmith who I will not name here but he lives in Kila, Mt and inquired about having my IAB 74 Sharps 45-70, 28" barrel throated out .300" because of the bullets I use a 550-gr Creedmore that need to be seated deep in the case, I want more powder in the case.  His response was, I don't want that peice of crap in my shop.  He flat out hates them period, and quite frankly is attatude stinks. :x

So I called another friend who just drilled and tapped the buckhorn sight for me that does have no paticulars about clone Sharps or the very nice Shiloh that I will be ordering soon.  It's just that I need a jump up right now from the standard 45-70 cartridge, and by throating up it creates a poor mans 45-90.  Timber Stevens now has my IAB and the cost is minimal to the purchase of a new clone outright.

I figure that ordering a new Sharps, needed to be done right and $250.00 down payment and a 10 month wait will put getting the new one past when I need it for the Quigley and other matches that are going on for the gong shoots that I want to attend.  Obtaining this won't be a problem at that time and I will more than likely order the 45-110 at that time.

Just wanted to pick some brains here of our more experienced BPCR shooters like Kenny and others and their thoughts on what I have done.  I know that some will say that throating out is useless to do, just ream it to 45-90 length and buy the 45-90 cases from Starline Brass and be done with it.

Whats your thoughts on this.

[rdnck]

Montanan--You're chasing your tail by 'THROATING" your Sharps.  Either chamber it for a 45-90, and then look at another $200 for cases and dies, or LEAVE IT ALONE AND SHOOT IT AS A 45-70.  If it were me, I would leave it as a 45-70.

You DO NOT need a 45-90 to be competitive at Quigley.  A 45-70 with a 28 inch barrel will reach any target at the "Q".  I shot a 45-90 there one year, and have shot a 45-70 there the last 2 years.  I will shoot a 45-70 there again this year.  Save your money for the Shiloh.  The 45-70 will get the job done.  Shoot straight, rdnck.

[Kenny Wasserburger]

Montanian,
    I have to agree with the Rdnck here, First of all he brings up one very good point for the gong matches you will be attending a 45-70 as is, will be more then enough gun! Most of these matches have a max range of about 800 yards. If your going to take the jump and do some reaming make it into a 45-90 and be done with it. However your IAB is a light rifle and it has again (now this is my opinion only sooooooo dont put it in the bank)  A poor stock Design for a 90. In other words its going to kick the snot right out of you.  

If throating is your wish I would not do it more then .100 that will get you into the range with Winchester brass of 78 or so grs of FFg Goex with a good bit of compression as is required.  Throating works-------- Ask Frank Monkowski He won a World Championship with one.  But even Frank does not advocate this method, not with good quality 90 brass to be had these days. To get a throated rifle to shoot is nother set of problems >>>> as Rdnck points out you will be chasing your tail on this, and it may never shoot as well as you want.

If it was me? I would leave the IAB as is, load with 68.5 grs of the newest Goex compress it over .300 to get the proper overall lenght to chamber in your IAB.  I would also suggest a bit lighter bullet as the 550 is often too heavy a bullet in a 45-70 and this comes from alot of experiance shooting them.  The Lyman Postell is in my opinion a much better bullet for your 45-70 or the 1881 bullet from Saeco, the Saeco 745 is also a good bullet but a bit lube challanged. For an off the shelf mould these 2 are hard to beat save the 550 gr bullet for your 45-110 when you get it! It wont take you but a few days to get eather of these bullet moulds and you will be up and Running for the Q in no time.

Now there is one gong style match where a 45-70 unless duplexed will leave you wanting as several of the targets are 900 yards and much father and thats my match. Only with Duplex will a 45-70 be able to shoot the Creedmoor match at my range and be competitive. Its at 900 where the 45-70 shows problems unless you have a MV over 1220 fps

With the New goex my 32 inch barreled Shiloh and a 520 NEI Postell bullet my MV is 1230 fps and this load will be competitive at Longer ranges. This combo was used by me at the recent World Creedmoor Assoc Match at Raton with very good results.  

Take care and good luck.

Kenny Wasserburger

[Cottonwood]

I want to thank you both for good honest answers here, I respect both of your opinions and your knowledge.

[TexasMac]

I read both rdnck's and Kenny's comments with great interest and it has me wondering why throating is not desirable.  Kenny you said "To get a throated rifle to shoot is nother set of problems".  Can you provide further details as to what problems throating creates?  By the way, my definition of throating is to add more freebore by removing a portion of the lands while insuring the diameter of the freebore does not exceed the bore diameter.  And I might add that I do not have any preconceived opinion as to the advantages or disadvantages of throating.  Just trying to get educated.  Thanks.
Wayne

[Kenny Wasserburger]

Texasmac,
   The best way for me describe it is to think of your carefully crafted bullet at .458-.459 in size it leaves the case and now enters said throat what space that was taken up by the case walls now the bullet will swage up to fit this space as it leaves the case. Upon entering the barrel proper it now was again be swaged down to the lands and groves Thats free bore.  However if the ball seat section (freebore that is under case size this problem will not be as bad) howver most throating is the same size as the outer size of the brass to be true freebore.

    A real good example is like shooting a 45-70 round in a 45-120 chamber this is a gross example but I am sure you get the idea.

As I mentioned in my first post proper lengthed ball seat can work well and most Shilohs have apox a .050 ball seat section infront of the point where the case terminates. As Frank M. had a .300 section in his 45-70 he used for the 1999 World Championship match and of course Won with this combo it can work but it presents a whole new set of problems to deal with . And in my opinion just makes for a longer learning curve to make a bp cartridge shoot well.

Dont get me wrong free bore or a proper ball seat will shot well but many old Shilohs with the so called freebore paper patch throat wont shot worth a tinkers damm  with bp loads and many have been rebarreled.

To each their own I guess, I prefer not to have to try to make something shoot that may or maynot ever shoot.

The reason Frank had .300 freebore was to make his 45-70 into a poor mans's 45-90 and did it at the time for very good reasons.  Some times proper terms help to understand the topic better.

Again opinions where asked for, this is simply mine. My goal has always been to lessen the learning curve for my fellow shooters. I have a very good friend that has a older C. Sharps ---Shiloh in 45-120 it shoots very poorly (on a good day) and plumb crappy most days.  Wheras my 45-110 Shiloh has aqquited itself rather well over the past 8 or 9 years and it  does not have the wonderful paper patch throat that my friends 120 does.

On more then one occasion with wittnesses this rifle has delivered 1 to 1.75 MOA groups at 200 to 1000 yards.  It is the only rifle to ever shoot a Clean 5/5 on the 864 yard buffalo at Raton in the old buffalo match that used to be held there after nationals.  Couple  years ago At my own creedmoor mtach I put 5 shots into less then 15 inches at 900 yards, this year at Raton at 800 I put my first 5 shots in a 13 wide x 10 tall group at 800. My good friends 45-120 wont shoot that good a group at 200 yards.

Granted shooting well helps, but the best shot cant do well with a 5 MOA load or rifle.

Kenny Wasserburger

[TexasMac]

Kenny, thanks for the additional comments.  From a theoretical point of view (since I have not tried it yet) I sure would expect that additional free bore or ball seat (I use the terms interchangeably) would have a negative effect on accuracy if the diameter of the freebore region was larger than the bullet diameter inside the case, especially if the bullet is not designed to match the freebore region.

My interest in throating is two fold, to add additional powder capacity, but primarily to aid in bullet alignment.  In other words, If I throat out a bore, say 0.3", and have a mould/bullet designed to match the freebore I believe it will help align the front portion of the bullet.  If the rear of the bullet is held by the case that has been properly sized to match the chamber than the bullet should be in perfect alignment, front to back, prior to being fired and undergoing obturation.  Using a bore-riding design is another way of accomplishing this but allows for more obturation and therefore, I believe, more potential accuracy degradation.

I have rifles with three calibers, .40-65, .45-70, and .45-90.  The .45-70 has absolutely no freebore.  The .40-65 and .45-90 have freebores of 0.1" and 0.15" respectively.  The freebore diameters of the .40-65 and .45-90 are 0.003" larger than the bore diameters, but should not be a problem since both are smaller diameters than the bullet diameters inside the case.  I may have the .45-70 throated and have custom moulds made for all three to try to take advantage of the freebores. We'll see.

I value comments from you and other very experienced shooters since I don't have much actual shooting experience to draw from.  Thanks.
Wayne

[TexasMac]

Kenny, I just realized I have a typo in my previous message.  In the 2nd to last paragraph I said

"The freebore diameters of the .40-65 and .45-90 are 0.003" larger than the BORE diameters, but should not be a problem since both are smaller diameters than the bullet diameters inside the case."

I meant to say was the freebore diameters of the .40-65 and .45-90 are 0.003" larger than the GROVE diameters.............  
Wayne

[TexasMac]

And I see I made another mistake in my earlier post.  Free Bore and Ball Seat are not one in the same.  Actually per SAAMI definitions Ball Seat, Chamber Leade and Throat are the same.  Sorry for the screw up.  Hope it does not confuse anyone.  I need to be more vigilant when using chamber terminology.

Not to get off subject, but I thought I'd list the actual SAAMI definitions for Free Bore and Chamber Leade.

Chamber Leade is the conical part of the bore between the chamber and the riflings.  Also called Throat or Ball Seat.

Free Bore is a cylindrical length of bore in a firearm just forward of the chamber in which rifling is not present.  Associated with bullet jump.

I'm currently in discussions with SAAMI on the definition of the transition region where the diameter changes from the chamber to the bore region.  If there is no Free Bore, which is the case with SAAMI spec’d .45-70 chambers, this conical section is considered a part of the Chamber Leade.  But if the chamber has Free Bore this section is not defined by SAAMI.
Wayne

[Cottonwood]

Well, the throating question is long gone......

I called my Gunsmith and he had the rifle apart so I told him to just ream it out to 45-90  :grin:

My 28" weighs 10.25 lbs, just a bit under what another freinds roller weighs and his is a 45-90 as well.  If I get slammed from recoil, I know I was forwarned and will love it anyway.

I really do appriciate all the advice though.  

[Lead pot]

Montanan>you made the right choice.Just grid your teeth a little more and roll with the recoil,it aint bad.Lp.

[Slick Fork]

TexasMac, Kenny W. and Montanan
Throating does create a increased learning curve as Kenny pointed out.(thanks Kenny, now I understand the whys) My Pedersoli rolling block is a 45-90 with a .3" freebore and as yet I've not figured out the correct way to load it. One 5 shot string made a 2"x4" group at 200 yards. That was the only group out of 450 rounds fired that was actually a group, all other 5 shot strings were shotgun patterns. I even loaded up 25 rounds with the bullet seated out to engage the rifling which exposed 2 gg on a 457125 bullet. They didn't shot well either. If there was an experienced bp shooter close by I would ask for his help to try and make it shoot accurately. As it now stands I will send it to a gunsmith and have the chamber cut off and chambered again as a 45-90 with no freebore.  I bought the gun used and didn't immediatly do a chamber cast. If I had I don't believed I would have wasted so much lead down range trying to find the "load".
Slick Fork

[Charles Vail]

My 45-70 has a chamber cut with a reamer from Dave Kiff of Pacific Tool and I beleive it has a long "throat" that allows me to seat my bullets out a couple of grease groves. My limited experiece has shown it easy to get good accuracy (1.25") at 200 yards after firing 5 rounds and using a blow tube. While only a three shot group my sighters were around 2 inches apart as I worked my way to the bull. I don't know if the Kiff designed reamer has a "throat" as large as the chamber or not but I think it tapers down to a smaller dimension just looking at the chamber from the breech. I will check my reamer and measure it immediately ahead of the chamber area and report! I think in a properly designed reamer with an intregal throated section, performance ought to be as good as a standard chamber.  If the chamber is reamed after the chamber is cut there is a possibility that a "too large" throater can be used. While I am not yet an experienced BPCR shooter I have done quite a bit of shooting in modern 1000 yard BR and have found it surprisingly easy to get good accuracy out of my rifle. A second 38-55 is in the works with a .150" throated chamber which I hope gives me simular performance. I just can't get enough of these old rilfes and that stinky powder,  what a blast!  :-D

[Cottonwood]

Well I got the Sharps back reamed up to 45-90... got out and did some testing while the weather was in a lul and temps were up in the 40's.

How sweet it is, I shall not look back, but continue forward  

[HWooldridge]

I have been fighting the "throating" question for a long time.  I have a Farmingdale Shiloh Sharps in 45-70 that is free-bored about .500 inch.  I bought it brand new in 1981.  It shoots jacketed bullets over smokeless into tiny little one-hole groups, grooved lead bullets less well and paper patch bullets not very good at all (which, of course, is what I am trying to shoot!).  Based on my experiences, I would not throat a rifle but would instead try to get a small enough bullet to slip into the bore with BP fouling present.  I think the comments above are correct in that the upset into the throat and back down to bore size are bad on a bullet.   A hard jacketed slug is not affected but a soft lead bullet doesn't care for the treatment.