dinker with this, do you believe it?

[foxhunter]

according to this my 17 v-raptor only has an accuracy life of just over 600 rounds.

http://www.websitetoolbox.com/tool/v...6mmbr&id=82966

[trotterlg]

Says my 17 Remington will live for 1181 rounds. I don't know if I would believe it, I would think bullet weight, velocity and what the barrel is made from would be a factor. Larry

[GLWenzl]

I don’t like it!! Or I should say it doesn’t like small calibers…. I could not get it to do my 17 Short Magnum, 17 CCM or a 17 Squirrel no matter what pressure I put in, it seemed to give up after maybe 10 grains of powder…..

I do think it is neat though and did play with it. Found it real interesting however it gets back to that pressure thing and unless you really know the pressure it is still a guess….

Also been learning this excel thing ever since another post so it gave me some practice!




The 17 AH was at 55000 PSI I am sure that is too much...

[Dave Moore]

once again look at the numbers and the cartidge at the top is the 17 AH, just goes to show what we have been saying all along "everybody should have a 17AH".


Dave

[GLWenzl]

I was particularly interested in how the numbers changed with the 20 BR just going from Ramshot Tac to N-540. Or from Big Game going from a 40 gr bullet to a 50 gr bullet....

This time I used 63000 PSI as I felt that was more accurate but have no way of knowing....



The first four all 40 gr V-Max and all are very close to just over 4000 fps, then I added a 40 gr with Big Game and the 50 gr bullets info as well...

[Alan in GA]

I'm over 5,000 through my 17 Ackley Hornet. Still puts bullets inside 1/2" @ 100 yards.
Don't ANYONE show it that chart!
98% of all loads were 20Vmax over 12.4/1680.

[foxhunter]

I guess here is why i have a problem with the figures the calculator Spitz out.
17 v-raptor 20 gr vmax load, 1680 powder, the case has a 52000 max pressure rating. how could a 17 ah with more powder at the same or more pressure have a longer accuracy life?
when you drop the powder charge to 10 the accuracy life is almost 50 % less.

Accurate Barrel Life
Bullet dia [in] 0.172
Loaded Powder [gr] 10.4
Powder heat potential [KJ/Kg] 4018
Pressure [Psi] 50000
Moly Coating [Y/N] n
Total 1266

Accurate Barrel Life
Bullet dia [in] 0.172
Loaded Powder [gr] 10
Powder heat potential [KJ/Kg] 4018
Pressure [Psi] 50000
Moly Coating [Y/N] n
Total 692

using comander spock like logic says there has to be a big flaw in this program

[GLWenzl]

I am not sure if this will pertain to the question you have brought up but here is my take on that (from how my lil mind is interpreting it….) Something I have been wondering about since you posted this darn chart!

Notice on the last chart I posted comparing the 20 BR loads….



IMR 4320 and Tac (1 grain difference) both get near the same barrel life where as N540 falls short well over 400 rounds with near the same powder charge….) All three loads are running very close to each other, just over 4,000 fps. This was a surprise to me and if I was in Vegas would have bet the farm that 4320 was the hardest on my barrel…

Now let’s look at just Big Game, I really thought this was a mild load with good barrel life but didn’t use it because the compressed load would not get the velocity I wanted.

I understand that it is burning 3 ½ grs more powder but appeared to me what would have been a mild load. I was surprised to see it shorten the barrel life as much as it did….. But then comparing it with the 50 grain bullets, it gets around 200 more rounds and even beats N550 which has less powder by weight….

If the guy who put this chart together knows what he is doing and it is in fact accurate I think it is a neat tool to help find the best powder load combination with longer barrel life especially like with my 20 BR where it shot most all of those loads in nearly the same groups (at 100 yards)

Like I said it may not be what you are asking but the powder (1680) may be what is hard on the 17 v-raptor and really needs to have a larger charge to get it to burn correctly???? Just a thought and I also realize 1680 is a powder of choice by some in the dinky 17 CCM case...

Another thing about this is by looking at the info one could be critical the VV powder charges (which I am not yet) and say they shorten barrel life (VV powders used in this comparison) but here is what VV has to say about their 500 series powder...

*Geometrically the powders in the N500 series are equal to the N100 series. Although these new powders have a higher energy content, they do not cause greater wear to the gun. This is because the surface of the powder has been treated with an agent designed to reduce barrel wear.

[GLWenzl]

Bob I just ran 1680 one grain at a time at 50,000 PSI no moly and this is what it spit out…

12 gr 1680=2835 fps
13 gr 1680=3117 fps
14 gr 1680=3136 fps
15 gr 1680=3011 fps
16 gr 1680=2815 fps
17 gr 1680=2591 fps

Right or wrong the info appears to be around 14 gr of 1680 for the longest barrel life???

[English Marv]

Please, on no account run the numbers for my 20-250. Thanks!