Freebore

Discussions of powders, bullets and loading information.

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Bad Bill
Posts: 1300
Joined: Wed Dec 27, 2006 9:44 pm
Location: SW of NE ND

Post by Bad Bill » Fri Jan 15, 2010 9:14 am

I have one with a freebore too. Will say one thing - it is easy to load for :o And, it doesn't foul up where you have trouble pushing the cartridge in because of crud buildup. Good hunting chamber.

Minnesota AL
Posts: 612
Joined: Wed Jun 30, 2004 4:39 pm
Location: St Paul MN

Freebore

Post by Minnesota AL » Fri Jan 15, 2010 5:50 pm

Kurt,

I'm ashamed to post a photo of the cast I made after I see yours. I'm a real rookie, lots of pock marks in the cast. I'll see about a photo.

The cast I have shows a freebore that is about .600 long, quite a bit longer than yours.
Minnesota AL
Uriah SASS#53822

Kurt
Posts: 7982
Joined: Wed Oct 12, 2005 10:28 pm
Location: Not Far enough NW in Illinois

Post by Kurt » Fri Jan 15, 2010 6:32 pm

Al that cast is really not the best, I got to much hot air on it and it brought up a lot of frosting.
I was just wondering if the taper started at the case wall and went down to the lands. My taper is a 5 degree and it is .128" long.
I got a cast from a original Sharps that is .400" as close as I could measure it. I have had old Remington's that had a very long taper like you mentioned.
I have a .40 caliber High wall that has a .243" long taper and that is working very good with a patched bullet .004 over bore diameter.
The old Remington's I had to patch to groove diameter and the grooved bullets I had a old mould that came with the .44 Rem had the ogive at groove diameter, with out the bore riding step, like a PP bullet with lube grooves.

No need for a picture of the cast Al.
Thank you.

Kurt
The reason a dog has so many friends is because he wags his tail instead of his tongue.

"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery"Winston Churchill

semtav
Posts: 2212
Joined: Wed Feb 03, 2010 3:21 pm
Location: Montana

Re:

Post by semtav » Mon May 03, 2021 6:55 pm

Vbull wrote:
Thu Jan 14, 2010 4:46 pm
Pretty much what Kelley wrote. When Dave and I started shooting long range BP cartridge matches, the canadians were the only game going. They had been doing it for quite some time and had settled on 45-70's shooting 15-20% duplex loads. Rifles were predominatly Martinis and Rugers with Central (click adjustable) sights. There was also a "Spirit of the Original" (Traditional straight black) class. We both originally competed with Shiloh's shooting straight black. (40-65 and 45-70) It did not take long before we both built rifles with freebored chambers to get more horsepower. Since we wanted some way to shoot long range without using duplex loads, we settled on a freebored chamber.

15+ years ago, 45-90 cases were hard to come by. There was some stretched brass and basic brass cases but not too much else. Plus it was expensive!

Back then, there were 2 different ways to get the .45-70 case to perform as a .45-2.4. One way was to freebore the chamber .300" at groove depth. The other way was to use a 2 diameter bullet that allowed the bullet to seat out into the rifling with just the base sitting in the case. Both ways allow a .45-70 case to hold 85 gr. of powder. You can get more in if a collar is used and the powder compressed down into the case.
If a freebore is cut correctly, it also helps align the bullet in the barrel. (but so does a correctly sized bore riding bullet nose) These are strictly target rifle chambers as the lube grooves are exposed to whatever. With the availability of good .45-2.4 and longer brass, it is no longer necissary to freebore a chamber.
Dave and I both still use those rifles built almost 20 years ago for target matches and they still perform. My roller (dog fight gun) has been setup as a long range scope class rifle.

I cannot comment on why the original owner of Shiloh freebored his rifles. Those I've seen and shot had the freebore cut too large in diameter for my liking but they shot good if a custom bullet mold was made to fit the freebore. Frank Monikowski


Thought this little piece of history was interesting.

Especially the part about the dual diameter bullets.

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