The Wiry Irishman
Member
An MOA 1911? I would love to hear more about this.
Freeboring .45 acp
- Thread starter Venado
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An MOA 1911? I would love to hear more about this.
combatantr2
Member
- Joined
- Nov 21, 2005
- Messages
- 251
so im wondering...
is it safe to freebore my glock???
is it safe to freebore my glock???
JohnBT
Member
"Thanks again
Jerry"
________
You'll get no arguments from me sir. I heard about you years ago when I didn't have any money and then when I finally got some I saw on the APG site that you were backlogged and not taking in new work.
I don't shoot pistols well enough to need one of your creations. I just like well made guns.
John
Jerry"
________
You'll get no arguments from me sir. I heard about you years ago when I didn't have any money and then when I finally got some I saw on the APG site that you were backlogged and not taking in new work.
I don't shoot pistols well enough to need one of your creations. I just like well made guns.
John
woad_yurt
Member
My Star MOD 30MI has a bit of freebore from the factory. I didn't know that that process was also done as a later modification on other weapons.
I do know that my Star is one very accurate mofo. I wonder how much the freeboring has to do with that.
Every now and then, I get some info that makes me even more impressed with those Star guys. It's a shame they no longer make guns. They incorporated a lot of cool features into that gun.
I do know that my Star is one very accurate mofo. I wonder how much the freeboring has to do with that.
Every now and then, I get some info that makes me even more impressed with those Star guys. It's a shame they no longer make guns. They incorporated a lot of cool features into that gun.
Badger Arms
Member
Snake oil in your bore will also work!
Seriously, there are DOZENS of things to do on a pistol before you mess with the bore to make it more accurate. Try lapping the rifling. That'll do essentially what you've said without possibly creating headaches. Don't have any problems with increasing the 'forcing cone' (so to speak) ahead of the chamber on a 45, but if a little is good, how about alot. Why not take out the rifling to halfway down the barrel? Why not take it all out!? Velocity will jump alot if you do that, right?
Where do you draw the line? I think the manufacturers have it about right now. Not that there isn't room for an opinion, but I'd like something other than 15 posts and your word. It doesn't work out in my head that lengthening the freebore on a .45 pistol will increase accuracy with a variety of bullets. Maybe a longer bullet or one seated backwards, but half an inch is lotsa jump.
... oh and remind me NEVER to buy a used gun from you.
Seriously, there are DOZENS of things to do on a pistol before you mess with the bore to make it more accurate. Try lapping the rifling. That'll do essentially what you've said without possibly creating headaches. Don't have any problems with increasing the 'forcing cone' (so to speak) ahead of the chamber on a 45, but if a little is good, how about alot. Why not take out the rifling to halfway down the barrel? Why not take it all out!? Velocity will jump alot if you do that, right?
Where do you draw the line? I think the manufacturers have it about right now. Not that there isn't room for an opinion, but I'd like something other than 15 posts and your word. It doesn't work out in my head that lengthening the freebore on a .45 pistol will increase accuracy with a variety of bullets. Maybe a longer bullet or one seated backwards, but half an inch is lotsa jump.
... oh and remind me NEVER to buy a used gun from you.
I just got back from chronographing the two loads I refered to earlier. One in a non-freebored gun, and the other in my gun that has been freebored and firelapped. There was 155 f.p.s. difference between the two loads. Two reinterate what went on, I had loaded a load in the nonfreebored gun that was starting to show signs of pressure with the primer. It was a load by the book for a 240 grn. bullet, but I used a 250 grn., that is why the pressure signs. I then duplicated the load in my freebored gun, and worked up from there trying to duplicate the primer from the other gun. Then chronographed. The difference was 2.4 grains of powder and 155 f.p.s.
Relationship of Bullet Diameter, to any specific Barrel's bore diameter....is often overlooked.
Barrels can vary a little...and for any given Barrel, an optimum diameter of Bullet, or diameter for Bullet type, should be possible...even if everything else remained the same.
The geometry of how the Rifeling begins, and where it begins, seems definitely important to my imagining the early stages of interior Ballistics.
Is the Rifeling indifferenly plowing grooves into the Bullet?
Or, does it oblige the Bullet to flow into it?
Bullet Alloy...hardness...how readily the Bullet upsets in it's initial phases of forward motion, to fill-out into the Rifeling...and the mechanical resistanes the Bullet is meeting as it does so...
Lots going on there in that first half-inch of forward motion...
So Venada, your Free-Boring...how does the Rifeling begin?Is it gradual, tapering? Or, abrupt?
Barrels can vary a little...and for any given Barrel, an optimum diameter of Bullet, or diameter for Bullet type, should be possible...even if everything else remained the same.
The geometry of how the Rifeling begins, and where it begins, seems definitely important to my imagining the early stages of interior Ballistics.
Is the Rifeling indifferenly plowing grooves into the Bullet?
Or, does it oblige the Bullet to flow into it?
Bullet Alloy...hardness...how readily the Bullet upsets in it's initial phases of forward motion, to fill-out into the Rifeling...and the mechanical resistanes the Bullet is meeting as it does so...
Lots going on there in that first half-inch of forward motion...
So Venada, your Free-Boring...how does the Rifeling begin?Is it gradual, tapering? Or, abrupt?
JohnBT
Member
"I just got back from chronographing the two loads "
I'm still paying attention, but right now I'm off to sit through a 3-hour staff meeting. I'm glad somebody is out having fun.
I'll read your post later.
John
I'm still paying attention, but right now I'm off to sit through a 3-hour staff meeting. I'm glad somebody is out having fun.
I'll read your post later.
John
Jim Watson
Member
Hmm, freebored barrel makes possible heavier powder charges and higher velocity.
Let's call it a ... Weatherby.
Interesting it should work at the pistol level.
I wonder how far you could extend the smooth throat and still spin up the bullet for reasonable accuracy. Maybe you could invent the Paradox handgun, too.
Let's call it a ... Weatherby.
Interesting it should work at the pistol level.
I wonder how far you could extend the smooth throat and still spin up the bullet for reasonable accuracy. Maybe you could invent the Paradox handgun, too.
Jim,
A person can get a lot more velocity out of the freebored gun. In fact that is what I am in to, the accuracy just came along with it. The two loads I chronographed were:
non-freebored: 963 f.p.s. /515 f.p.m.e.
freebored: 2.4 grns. powder difference 1118/694
That is with a 250grn. LRNGC
These loads did use a bullet lube that I made that probably helped out a lot.
This was just a test, I have gone way beyond with jacket bullets, but don't want to get kicked off here by saying just what has been done.
A person can get a lot more velocity out of the freebored gun. In fact that is what I am in to, the accuracy just came along with it. The two loads I chronographed were:
non-freebored: 963 f.p.s. /515 f.p.m.e.
freebored: 2.4 grns. powder difference 1118/694
That is with a 250grn. LRNGC
These loads did use a bullet lube that I made that probably helped out a lot.
This was just a test, I have gone way beyond with jacket bullets, but don't want to get kicked off here by saying just what has been done.
1858rem
Member
wow! that is some amazing velocity man but please dont list the complete load some no one else tries it and gets hurt. i was backing off 255g cast bullet loads at 775 fps lol
ROBBY.1911
Member
- Joined
- Mar 8, 2007
- Messages
- 225
how can you say the .45 acp headspaces on the case mouth, when in reality it is positioned in the chamber by the extractor. iam no expert, just trying to learn something. the extractor grabs the round before anythng else happens. like i said, i'm no expert.
1911Tuner
Moderator Emeritus
Because it does. The extractor doesn't grab the round. The cartridge slides upward on the breechface and under the extractor during feeding...but the extractor doesn't bear against the forward part of the rim until the case is extracted.
Assuming minimum chamber depth and mid-spec case length...the case only has .005 inch deeper to go until the mouth contacts the chamber stop shoulder. Even if the static headspace dimension is .910 inch, and the case is .888 inch...or minimum spec...the firing pin will shove the case forward in the chamber until it contacts the shoulder...thus headspacing the cartridge.
The case will headspace on the extractor only if either the chamber depth is far out of spec, or the chamber is nearly so AND the case is minimum length or below. Even then, the chamber would be so far out of spec that the gun would fail the standard NO-GO gauge test.
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