+P chambers

[Coyote Shadow Tracker]

I was limited to reading the forum the past month or more and am late to this dance. If you want to get more velocity out of your cartridge why not just chamber it to an Ackley Improved?
Is the purpose of chambering to a +P by decreasing the Land's height after the freebore to get extra velocity with max powder fill of the case? Doing this to take out the extra step of "Fireforming" the Case for an AI to get more FPS?

We always try to match the Case/powder/bullet for the cartridge we want to get the best acceptable performance of Accuracy.
I do admit that we chamber and have 338LMAI to get more Velocity, but realistically the 338LM is just a great cartridge the way it was designed.

I think that there are hundreds of "Wildcat" Cartridges and changing the SAAMI dimensions is a way for, sometimes, improvement in our Sport.
If we didn't have shooters experimenting, we would never have advancements.

Probably off the main topic of Warranty. If you look at manufactures of firearms most have a "Clause" that their warranty is void if you don't use New Factory Ammo.
I can't see holding a manufacture responsible if you modify their product/components.
Just a thought.

 

[fordy]

Gday coyote shadow chaser

I was limited to reading the forum the past month or more and am late to this dance. If you want to get more velocity out of your cartridge why not just chamber it to an Ackley Improved?
Is the purpose of chambering to a +P by decreasing the Land's height after the freebore to get extra velocity with max powder fill of the case? Doing this to take out the extra step of "Fireforming" the Case for an AI to get more FPS?

We always try to match the Case/powder/bullet for the cartridge we want to get the best acceptable performance of Accuracy.
I do admit that we chamber and have 338LMAI to get more Velocity, but realistically the 338LM is just a great cartridge the way it was designed.

I think that there are hundreds of "Wildcat" Cartridges and changing the SAAMI dimensions is a way for, sometimes, improvement in our Sport.
If we didn't have shooters exterminating, we would never have advancements.

Probably off the main topic of Warranty. If you look at manufactures of firearms most have a "Clause" that their warranty is void if you don't use New Factory Ammo.
I can't see holding a manufacture responsible if you modify their product/components.
Just a thought.

Just a query in your post do you mean exterminating or was it meant to be experimenting

Cheers

 

[fordy]

& meant to be tracker not chaser sorry
Cheers

 

[Coyote Shadow Tracker]

& meant to be tracker not chaser sorry
Cheers

Fordy
Thanks much!
I should not be on the Forum Posting late at night and not trust spell check.

Thanks
Len

 

[Dean2]

I will bet there are guys that will do a +P chamber even after reading this thread. Seems there are always those who want to get a 250 grain bullet to 4000 FPS, even if the barrel will only do it twice.

 

[ARlife4me]

I will bet there are guys that will do a +P chamber even after reading this thread. Seems there are always those who want to get a 250 grain bullet to 4000 FPS, even is the barrel will only do it twice.

 

[QuietTexan]

I will bet there are guys that will do a +P chamber even after reading this thread. Seems there are always those who want to get a 250 grain bullet to 4000 FPS, even is the barrel will only do it twice.

I mean why not? Shawn says he can +P what I was going to send him, it's not like a 300 LIMP in a Defiance action, carbon fiber barrel, using N570 is going to last more than a couple hundred anyways. If I can get 150+FPS more without barrel life dropping into the double digits, I'm game. It's already a toss up between lug setback and getting the barrel too hot one time as to what kills it, alls I'm doing is putting one more horse in the box for the race.

But at least I'm going in eyes-wide-open knowing that I'm removing a measurable amount of metal every time I shoot it.

 

[ARlife4me]

I mean why not? Shawn says he can +P what I was going to send him, it's not like a 300 LIMP in a Defiance action, carbon fiber barrel, using N570 is going to last more than a couple hundred anyways. If I can get 150+FPS more without barrel life dropping into the double digits, I'm game. It's already a toss up between lug setback and getting the barrel too hot one time as to what kills it, alls I'm doing is putting one more horse in the box for the race.

But at least I'm going in eyes-wide-open knowing that I'm removing a measurable amount of metal every time I shoot it.

There you go....full disclosure! Admittance is great! I wish my P O S neighbors were the same way!

 

[VinceMule]

The +p section will not last 100 rounds, then you just end up with more throat, right?

 

[ARlife4me]

The +p section will not last 100 rounds, then you just end up with more throat, right?

probably varies on end user's use

 

[Northkill]

The +p section will not last 100 rounds, then you just end up with more throat, right?

You'll lose velocity to get accuracy.

 

[MtPockets]

What about nitriding?

Is that helpful and/or worth the extra cost in notorious barrel burners?

 

[Northkill]

What about nitriding?

Is that helpful and/or worth the extra cost in notorious barrel burners?

Never tried nitride myself. I'd definitely look at doing the 400MOD harder SS for hotrods. Very happy with mine so far. 7 Allen Mag and 27 Nosler.

 

[jensenj71]

I have zero hesitation using DE +P in the right application. I feel like I understand the the pros and cons. I also use N570 when it produces the desired results on a target at 600yds. If H1000 is more consistent I will happily take the lower velocity and many of my loads are H1000.

I understand that my barrel will not last 800+ rounds and my barrel will start to degrade around ~400 rounds. I am not asking for a barrel warranty. I don't care if someone else thinks ~400 rounds is unacceptable.

I tend to run normal pressures at the expense of wear and tear on the consumables (barrel). I see loads posted from time to time that seem well in excess of the normal pressure. I would rather run a +P chamber at normal pressures than a standard chamber at max pressures. In my mind, if you are matching my velocities with H1000 and a standard chamber then you are running much higher pressures and stressing all of the parts that see the pressure. I certainly see the logic of normal pressures with a standard non +P chamber.

I would not run a +P on a high round count rifle. I would not run N570. If I expect good barrel accuracy out to 1000 rounds I am also not going to run a barn burner cartridge such as 28 Nosler, 300RUM, 30-378, 338 Edge, 338 Lapua Improved, 33XC. I am going to run 6.5CM, 308WM, 338NM.

My point is that there are numerous choices that contribute to barrel life and +P is just one of them. In my mind +P makes sense for a few of my projects where I am searching for performance rather than longer barrel life.