Here is a video that explains what + P is from defensive edge.
338 Edge+P vs 338 Terminator vs 338 Norma+P
- Thread starter DirtNap35
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It shaves your throat it's so pressure isnt instant. You shave it you lose it. Never seen a +p last longer then without.
Don't know what we're trying to kill but the 265 ABLRs have a BC G1 of .732 and a .331 SD and can easily be pushed to around 3100fps from a 338 RUM + P with a 26" barrel. Additionally they fit in the Wyatt's box and carry more than 1500 ft. Lbs. beyond 1300 yards and gets to a grand in just over a second, 1.23 to be precise. Again I just have never needed more. The ABLR and ELDX are better hunting bullets than the 300 OTM from Berger in my humble opinion. Love my RUM! Easily one of my favorite rifles.
I respectfully disagree. I own two +P chambered rifles the 338 and a 280 AI. It is exactly because of the reduced pressure that the barrel last longer.If you are really pushing it then a reduced barrel life is to be expected. I can run 300s at 2900 but the accuracy node is at between 2750-2850 with more than enough energy and velocity to kill an elk beyond a grand, so why would I push it harder than that. Further more to get a standard chamber to duplicate the +p you have to push up the pressure thus prematurely eroding the throat. Either way you go there is a trade off. For me the +P is a fairly ingenious design and like Ackley substantially improves the performance of some cartridges. JMTs
I respectfully disagree. I own two +P chambered rifles the 338 and a 280 AI. It is exactly because of the reduced pressure that the barrel last longer.If you are really pushing it then a reduced barrel life is to be expected. I can run 300s at 2900 but the accuracy node is at between 2750-2850 with more than enough energy and velocity to kill an elk beyond a grand, so why would I push it harder than that. Further more to get a standard chamber to duplicate the +p you have to push up the pressure thus prematurely eroding the throat. Either way you go there is a trade off. For me the +P is a fairly ingenious design and like Ackley substantially improves the performance of some cartridges. The terminator by design has a +P chamber as do many LR competition rounds. My chamber gets me 200-250 fps over a standard chamber and around 100 fps over the edge. JMTs
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if half the lands are removed you started with half the lands. Powder like n570 will eat the lands in 900 rounds on a lapua improved. You remove material you dont get it back.
Half of the lands aren't removed. +P is not the same as freebore. It is a graduated chamber. The bullet still engages the lands the same as a standard chamber but with reduced pressure. It helps to see a diagram of it. Again either way you go there will be trade offs. I do agree with you that the 338 Lapua AI is probably the best option for the OP's intended purpose but the 338 RUM or Edge in a +p configuration would be good options as well. When talking hunting rifles practicality and efficiency are my primary concerns. I want a rifle that is handy and maneuverable and not to heavy. The efficiency matters because I can shoot it more in order to become more proficient with it, which is far more important than being able to go super fast. With the 285 Flatliners I can stay supersonic to 2600 yards. Again what more could you ask for? The more overbore the cartridge the less barrel life regardless of the chamber configuration.
I know exactly what it is. Its not throating thats correct. Throating is removing the lands too desired length. +p is shaving the lands there on out so you reduce the pressure to add more powder. You add more powder you get more heat. With more heat you get faster erosion. You got less material at the end of your throat where your lands take off. Less material + more heat = less barrel life. It does work for what it's designed for. Why i dont do them.
MagnumManiac
Well-Known Member
My 338 Edge +P on a 30" barrel still did not get me above 3,000fps with 300g Accubonds, Berger or even 285g ABLR, which is why I went with my own design.
Cheers.
I don't know that "lasts longer" is part of the discussion, but Paladin has 1k rounds down the tube with little sign of wear. That's a pretty good gauge of barrel life.
Have you got experience to back up the shortened life expectancy claim?
Not trying to pick a fight but I've been looking at the +P as well. The last thing I want to do is intentionally do something that will shorten the life of the barrel.
The extra speed would be great but not if it means changing barrels out more often.
If the desired barrel length is 26" and the desired velocity is 3000 fps with 300s, of the choices the OP gave the terminator is the only one that even has a chance. The Lapua AI +P would be the ideal choice for those parameters. I am not sure you need it but this is not a needs kind of thing.
6fatrat
Well-Known Member
11 pound Elk rifle, ouch.
My factory 338 RUM with brake and scope is just under 8 lbs
Steve Bair
My factory 338 RUM with brake and scope is just under 8 lbs
Steve Bair
With regards to barrel life, poor cleaning habits or bad cleaning practices and over pressure rounds do more harm to barrels than a +p throat, JMO and observations.
If you want 3000 in a 26" barrel with 300 Bergers then the obviius choice is the 338 Terminator. Broz has been running that combo for years and has seen results on hundreds of elk. Don't over think it. OAL is 3.930 so repeater works in BAT. Im running a Lapua and Lapua Improved with 30" Proof barrels. Node on Lapua is 2850 with H1000, on Lapua Imp its 2980 with n570. Both shoot 10 shot 1 moa groups at 1000. Shoot 3" three shot groups. Forget the silencer you need a brake. I fireform 50 pieces of brass and have 10 reloads on em in my AI.
