+P chambers

[WSnyder]

Boyer 6PPC Pure Magic Bore Rider.

 

[ebb]

Let me get this straight, someone convinces a shooter to cut half of the height of the lands away for a good distance down the barrel and then expects you to replace the barrel when the throat is gone, but hey cut half of it out with a reamer?? Am i understanding this right???

 

[dcali]

Let me get this straight, someone convinces a shooter to cut half of the height of the lands away for a good distance down the barrel and then expects you to replace the barrel when the throat is gone, but hey cut half of it out with a reamer?? Am i understanding this right???

That's how I'm reading it. Strange times...

 

[LVLAaron]

My guess is, the end users of these barrels don't fully know or understand what was done. They just bought some fancy sounding thing from a guy who says "bullet go more faster"

 

[Idaho-Lefty]

IIRC, the long throat is part of the reason Roy Weatherby attained his phenomenal velocities.

Yup,.. And SHORT Barrel Life !
I had, a .270 Wby 1-12 Twist that, "went South" at,.. 850 ish rounds ( One Day, the groups DOUBLED, in size ! ).
Thankfully I had another .270 Wby Barrel under my work bench, due to having 2, .270 MK-5 Wby's at the Time
( I made one into, a sweet, .338 Win Mag,.. thus the extra Bbl ).
Extra LONG, FB's / Throats, are just asking for Trouble,.. IMO
Frank G.,.. tell em' to, go pound sand, if NOT, a reasonable Throat / FB length

 

[swd]

I had a couple guys I built a lot of LR hunting rifles for. They usually bought their own reamers. The last 2 rifles they wanted built were 6.5x300 Weatherby’s. I got a call a few months later that they shot great for about 200 rounds and then stopped shooting. I bore scoped them and they were toast. They sent one barrel back to the manufacturer, it wasn’t Bartlein, and the manufacturer told them there was no way he’d warranty a 6.5x300 Weatherby for barrel life.

 

[Homerange]

Yup,.. And SHORT Barrel Life !

Not exclusive to Weatherby’s, but RUM's too.

 

[JTEX]

So building a bore rider is bad ......but an overbore monster like a 6mm creedmoor or a 22br is okay?

 

[snert]

m just bummed to learn that I shouldn't put a blower and nitrous on my Briggs and Stratton...

 

[Alex Wheeler]

The Boyer print is not a +p, its like a typical throat but with 2 angles. The +p is what should be called a stepped throat. I know a lot of people call it a bore rider but that doesnt make sense to me. Its mostly a long range hunter thing. Personally, I have shot enough ladders at 1k to see the windage difference on paper that 100 fps makes. Its nothing.

 

[William Vogel]

Let me get this straight, someone convinces a shooter to cut half of the height of the lands away for a good distance down the barrel and then expects you to replace the barrel when the throat is gone, but hey cut half of it out with a reamer?? Am i understanding this right???

My guess is that they don’t inspect their barrel with a bore scope when new and just chambered, maybe? Then 500 rounds later they look and see something that they never understood in the first place.

 

[ebb]

I think that the long and short of it is that there is no free lunch. And that William and Arron are right some of the surprise is when they did what someone told them was a good idea, but really didn't understand what they were agreeing to. I have read about the bore rider but had no idea it was the same or similar to the +P type of chamber. I had a guy talk to me once about chambers that was in love with the idea of a 1% lead, Is this the same thing ?

 

[Rsadams]

As one I can tell you if there's a warranty on race engines it's very limited most don't offer one at all.... Basically if we screw up the machining other than that it's your baby , bring it back when the season is over and we will refresh it for the next one.... We never had a problem of motors blowing up but by the end of a season there worn out and they damn sure didn't run 100,000 miles on a dirt track... Any modern motor should make it 200,000 miles if taken care of , I bet those motors don't run 2000 miles , it's what happens when you turn them 9000 rpm versus 2500rpm , run them hot , flat abuse them plus there built looser...

Same thing happens with barrels... Iam 55 and have my grandfather's guns that still shoot fabulous it's because they have been taken care of and in reality have had about three boxes of shells shot through them because he used them for hunting... You guys burn up that many shells in how long in a match..??? Same reason a fine over and under can easily shoot 500,000 rounds , the barrels don't wear , no rifling... My friend has won everything in sporting clays over the years I think he was last years national champion and shot for team USA this year and he said he could only take two shotguns to England but instead he was only going to take a spare release trigger because that's really all that will fail... If you remove half the metal before you start you only get half the life... That's if you're not abusing it in that case expect a lot less...

 

[rhovee]

I agree and have said this before. No free lunch with speed and less pressure. Try N570 out in an overbore magnum. You’ll find out real quick. Don’t see how it’s possible to run a +P and not have more throat erosion.

 

[Jud96]

I think it’s a cool concept, but if you’re going to drastically reduce barrel life for more velocity, I’d just step up to a bigger cartridge with a conventional throat. When I first learned about the +P throat I was fascinated and I was also much less experienced and much more naive at the time so I didn’t think of any of the negatives. I think it’s a cool concept, but I’m not sure if the juice is worth the squeeze.

 

[wjplohman]

I took it out .170 past the normal throat. All I can shoot in it now are the Hornadys and the 142-150 SMKs.

My max jam on the 147 Eldm is 2.970.
When the 135 atip came out I finally settled at 2.922 with around 0.070 of jump . Shoots great out to 1000 yards.running around 2923 ft sec. Been up to 2986 before the primers were flattening more than I like

 

[SeabeeKen]

So I'm throwing this out here and I'm going to be very blunt about it.

Here is my stance on +P chamber throats. You're cutting away the height of the lands as well as making the throat longer as I understand it and from what I've seen in several barrels (one barrel the throat was another .750" longer) customers have sent back to us. So guys think they can run a heavier powder charge etc... to get more velocity and keep pressures down. Ok fine but by doing that you can expect it to have a negative impact on barrel life/accuracy.

This is another variable beyond our control. You want to put a bigger camshaft in your cars engine and a bigger carburetor I get it but then you add nitro methane in your gas tank our put nitrous on it as well to go even faster.... there is a trade off for going faster. You don't get to eat your cake and keep it to.

So I've told all my guys in the office here... I will not warranty any barrel that a customer thinks the barrel died early etc... and they are running a +P chamber set up.

Later, Frank
Bartlein Barrels

Just stop offering it

 

[SKWERLZ]

Just stop offering it

They don’t offer it.

 

[SeabeeKen]

They don’t offer it.

Ahh, now i get it. Others are chambering them. Morning fog. Thanks

 

[charlie b]

I agree with others that you should be selective about your warranty. It should be based on borescope information and ONLY be applied if the barrel is defective is some way, such as an inclusion not seen during mfg or other metal issues.

I can see people doing a LOT of different things to barrels and chambers thinking they are going to be the next 'hot' thing. You should not pay for their experimental results.

FWIW, in cast bullets there is a specific use for "bore riders". They are stepped bullets, usually heavier than 'normal'. The stepped bullet allows them to be seated within the neck while the reduced nose of the bullet rests on the lands of the bore ahead of the throat. When done with a correctly sized bullet it is an interference fit, centering the bullet in the bore, and it can be quite accurate. I frequently loaded them such that the first drive band was jammed as well.