+P Throating

If I can get 200 rounds a year for 2-3 years out of this gun it will be good enough for me but i was hoping for 4-5. That was my deciding factor as its not a practice or varmint gun, its my elk rifle, it's just too expensive to feed to be running it any harder than that. When i practice long distance I usually don't fire more than 10 rounds out of it in a day, vs my 6 BR where I may kill a box of 100 on steel or a busy ground squirrel town.
 
I'm a bit confused...... Doing a +p on my gun lowers barrel life?
Yes, as Kirby explained the various +p/bore ryder type throats will allow one to increase velocity and are "nicer" to softer jacketed vld bullets as they engrave the bullet more gradually.

The downside is they will have a shorter barrel life because the shallower lands at the throat will burn out quicker then a standard throat due to being shorter thus they contain less steel.

The more powder being burned the quicker it will occur.
 
Yes, as Kirby explained the various +p/bore ryder type throats will allow one to increase velocity and are "nicer" to softer jacketed vld bullets as they engrave the bullet more gradually.

The downside is they will have a shorter barrel life because the shallower lands at the throat will burn out quicker then a standard throat due to being shorter thus they contain less steel.

The more powder being burned the quicker it will occur.
That is not entirely true. With the +p or my Hybrid throat, yes shorter barrel life. A True bore rider throat design does not have to be anything other then a conventional 1-30-00 leade angle but with no throat length at all.

a true bore rider bullet will have a bullet body that is nominal BORE diameter with the drive band which is nominal GROOVE diameter with the drive band being seated even or close to the case mouth. As such a conventional, long life throat design can be used, just with no throat at all.

i ran into issues years back with one companies bore rider bullets in my 375 Allen Magnum. We had used most of their 375 cal bullet offerings under 400 grains with great success in my standard throat chamber which had roughly a 0.300" long throat.

however once we started testing the 400 gr and heavier bullets, results were terrible. Long story short, some bore riders do not always work in standard throated rifles, especially when the bullets are extremely long and heavy and used in fast twist barrels at high speeds.

found that the drive bands could not hold the rifling after jumping to the lands. They would literally shear off. This bullet manufacturer said this would never happen with their bullets. However, once i had a reamer made that had a 1-30-00 leade angle right off the chamber mouth so i could seat the drive band right to the bullets there was not a single issue.

anyway, point being which i got way off track, a true bore riding bullet design can use a conventionally dimensioned leade angle with zero throat length which will result in a very long throat life.

a bore rider bullet in a +p or Hybrid throat would likely result on even shorter throat life….
 
Ok just for talking purposes if my barrel life was 3000 rounds, off the top of your head what would it be now with the +p saying that I'm going to load around 3 more grains. Not holding anybody to anything just asking for knowledge. Thanks.
 
Ok just for talking purposes if my barrel life was 3000 rounds, off the top of your head what would it be now with the +p saying that I'm going to load around 3 more grains. Not holding anybody to anything just asking for knowledge. Thanks.
Impossible to really predict. I can tell you in my testing, my 7mm Allen Magnum for example, with standard throat i was using around 102-103 grains of RL33 which produced around 3345 fps with a 180 gr berger out of my 26" long test barrel. on average with my standard throat we would see 800-1000 rounds of useful long range big game hunting accuracy life if cared for properly and used properly.

with my hybrid throat i had to drop to the faster burning Retumbo and used roughly the same powder charge at 103-104 grains with average velocities in the 3475 fps range in a 26" barrel length. Used and cared for the same way as my other test rifles, i was seeing noticable accuracy drop off at 300-400 rounds and total loss of consistency at 400-500 rounds. so in my testing it was 50% less and i was really careful with shooting the rifle.

this was similar in all my wildcats except my 338 Allen Magnum where is was reduced to around 1/3 regular accuracy life…..

so in your example, i would GUESS 1000-1500 rounds of useful life which sounds like a lot and certainly will last a long time if rifle is used in a certain way but again, half the life for same investment in barrel cost and fitting….. not worth it for my customers to offer as an option. Great deal if i wanted to replace barrels frequently for that income….
 
I was thought quite alot about even posting on this thread after becoming aware of its existence because I don't like internet ****ing matches. Here was our process and testing. Anyone is free to look up the patent to see the details and application. Kirby is 100% correct that it is nothing like Weatherby freebore. It is simply a step in the rifling leaving the bullet touch point in the same location, allowing spin and engraving to be started at the same time but at a much reduced pressure. By the time you add more powder to the round to get back to normal pressure you have the benefit of more powder burnt down the barrel increasing the velocity. This is the simple part and with certain case capacity exceptions people are seeing 100-125 fps increase in velocity. I too was concerned about potential barrel life so I turned a new 338 Edge, 1000 SMK's and a pile of H1000 over to my friend Sam Millard to test barrel life. I told him to shoot it anyway that he considered normal use, test the throat burn length, group size every 100 rounds and document it. At 1000 rounds the rifle still shot under 1/2 moa, still shot 2800 fps and the throat had only moved forward .018" if I recall correctly. I stopped testing it there being satisified with the results. As a side note a few 338 Terminators with this throat design burned up early due to the reames +p section not being built to my specs where it left only .0005" to .0010" of rifling in the +p section. Correction this dimension put barrel life back to where one would have expected it to be. I got short of 400 rounds out of my first 338 Terminator barrel and just over 800 out of the second after the new reamer was produced. These rifles like any can get burned up if you shoot them hot. I believe some people damage them because they don't understand how easy it is to ruin a high performance rifle.
 
Well I read everyone of the post here ...as a Shooter / Hunter I'm always looking for the Best we would call it .
I have been looking at Shawn's +P thoat for a long time .
Not sure if he remembers one early Sunday morning he actually answerd a question I had about one of 338 Edges . Well it helped me reach out to 3027 yards!
As I set here thinking about this I would jump on the +P Design!
Almost everyone on here is pushing there equipment as much as possible. I have never met a single person that shot out a barrel , I sure havent .

Its guys like Shawn , 50 Driver ect that has pushed me to go further and I Thank them alot !

This is a Long Range Forum and we all want the best we can have !
I would be very Happy to be one of the Guys testing and getting more from the +P idea !
This will push me get one to Shawn !

Just my two cents !

Rum Man
 
Almost everyone on here is pushing there equipment as much as possible. I have never met a single person that shot out a barrel , I sure havent .
I'll send you the last 7rum barrel I knocked out:D... It's sitting under my rifle bench. I was going to make a tomato stake out of it this year but forgot. It didn't even take 1,000 rounds to take the rifling to zero depth for the first couple of inches. I have a hard enough time getting a throat to last. I'm not really liking the idea of taking metal out of the throat for possibly 100 fps.
 
Some folks understand the limitations of a magnum and some don't. Then there are those that just don't care. If you run an Allen Mag I'm thinking you fall into the latter as burning barrels is a given. I'm sure it's fun if you can afford it.
 

Recent Posts

Top