Range Report Is an average of 2700 fps good?

[25MAN]

I have a custom built 260 by RWS Gunsmithing...it has a 24 inch Rock 1:8 twist barrel on it. after doing load development with the rifle it loves the 142 SMKs with 43grns of IMR 4350 (switching to H4350) and the average on the chrono came out to be 2700 FPS with the slowest around 2688 fps. The powder I was using was older so not sure if this affected anything.

Question is if I am going to be shooting out to 1000yds is 2700fps ideal or should i look to sacrafice a little accuracy for velocity?

Load data:
142grn SMKs
43grns IMR 4350
FM210 Primer
2.834 OAL

I have shot this to 300 to test it and it shoots 1 inch groups consitantly and capable of better as there was 1 group that measured under an inch.

Thanks for your input...

 

[jrob300]

Re: Is an average of 2700 fps good?

25MAN,

For that load, at that COAL in a 24, you *might* be close to as fast as you're going to get. My 26" will shoot 2875, but I get ejector marks. So I shoot 2780 and so far 1250 yds. has been no problem (the farthest I've shot it to date). Velocity will affect your wind holds a little but really only becomes an issue with regard to *maximum* range.

Don't look at the numbers, shoot it and you'll be fine.

John

 

[sandwarrior]

Re: Is an average of 2700 fps good?

It's a lot better to sacrifice velocity for accuracy. NOT the other way around. 2700 will get you where you need to go.

As a side note, I just went out to Nevada and one of the guys I shot with out there was using 123 Lapua Scenars and was hitting to one mile. He was handily beating my 7mm-08 @ 1k.

You might want to try the 123 class out of that case and see what the benefits are. The gained velocity will nullify windage loss in all but the strongest winds.

Edit:

FWIW: yes, I would get some better powder if I were you. I would suggest some RE-17.

 

[25MAN]

Re: Is an average of 2700 fps good?


Sandwarrior,

What length barrel was your buddy running and what type of velocities?

 

[blklabs]

Re: Is an average of 2700 fps good?

2700 is pretty slow. On my 24" Bartlein it was going 2800 with 43.5 gr of H4350. After a couple of hundred rounds, the velocity spiked to 2910 with the same charge. After that I lowered it to around 42 grains and was getting 2830. I don't know how many rounds you have done the tube, but if don't have many put several hundred through it and then redo your load dev and chrono. You might see your velocity creep back up.

 

[25MAN]

Re: Is an average of 2700 fps good?

blklabs,

190 rounds down the pipe. I am hoping that part of the issue was the 10 yr old powder. haha but in all seriousness all the reloadign data I see they claim 2700 or slightly over for 142s at 43grns.

I have loaded the new rounds with H4350 but according to Hogdons I will not see much difference in velocity, but I will see if i do get some gain or it might allow me to keep my current accuracy with highr grains of powder.

I will continue to put rounds down range but for now I have to deal with what I have to work with...hopefully over time it will gain some, but if not, I can always drop to a lighter weight bullet to gain velocity but I like the BC on the 142 SMK.

Just wanted to see if infact 2700 was going to surfice...I figured I was fine right there just needed some reassurance...of course I would love to be closer to 2800.

I'll keep playing around with it.

thanks

 

[blklabs]

Re: Is an average of 2700 fps good?

Its all about how flat do you want to go. When I was running it at 2910 I was 7.7 mils to 1k. With your load you are roughly 9.1 mils at 1k and you are going transonic somewhere between 1300-1400 according to JBM with a sight height of 2.1".

I am kind of surprised since Rock's tend to run fast. If you haven't shot the new powder yet, you might want to go down and work back up to your previous load if you weren't planning on doing that. H4350 is notorious for being inconsistent lot to lot, but very consistent within that lot.

 

[25MAN]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: blklabs</div><div class="ubbcode-body">Its all about how flat do you want to go. When I was running it at 2910 I was 7.7 mils to 1k. With your load you are roughly 9.1 mils at 1k and you are going transonic somewhere between 1300-1400 according to JBM with a sight height of 2.1".

I am kind of surprised since Rock's tend to run fast. If you haven't shot the new powder yet, you might want to go down and work back up to your previous load if you weren't planning on doing that. H4350 is notorious for being inconsistent lot to lot, but very consistent within that lot. </div></div>

Yeah and I guess that is what I am trying to weigh out now...I am a believer in the faster a bullet gets down range the less time elements can have an affect on them, therfore the better off I am...so for me the flattest and most accurate combination is what i am searching for. I myself am slightly dissappointed in the results of 2700fps was truly hoping for around 2750 0r above. But it is extremely accurate with this load.

 

[pcschwenke]

Re: Is an average of 2700 fps good?

25MAN, If you are trying to get about 2750fps, you may want to look at 2000MR. My loads stopped at 48.5 grains with the 175 SMK but it was not due to pressure signs. Velocities were around 2730 fps with a stock 24" Remington 5R in Federal brass. I tried to find a node near the Federal factory 175 SMK load.

Paul

 

[25MAN]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pcschwenke</div><div class="ubbcode-body">25MAN, If you are trying to get about 2750fps, you may want to look at 2000MR. My loads stopped at 48.5 grains with the 175 SMK but it was not due to pressure signs. Velocities were around 2730 fps with a stock 24" Remington 5R in Federal brass. I tried to find a node near the Federal factory 175 SMK load.

Paul </div></div>


I am going to make the assumption either you are shooting a 308 or meant to but a different bullet weight

 

[pcschwenke]

Re: Is an average of 2700 fps good?

Yup, Sorry for the mistake. Didn't realize you're shooting a 260.

 

[blklabs]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 25MAN</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: blklabs</div><div class="ubbcode-body">Its all about how flat do you want to go. When I was running it at 2910 I was 7.7 mils to 1k. With your load you are roughly 9.1 mils at 1k and you are going transonic somewhere between 1300-1400 according to JBM with a sight height of 2.1".

I am kind of surprised since Rock's tend to run fast. If you haven't shot the new powder yet, you might want to go down and work back up to your previous load if you weren't planning on doing that. H4350 is notorious for being inconsistent lot to lot, but very consistent within that lot. </div></div>

Yeah and I guess that is what I am trying to weigh out now...I am a believer in the faster a bullet gets down range the less time elements can have an affect on them, therfore the better off I am...so for me the flattest and most accurate combination is what i am searching for. I myself am slightly dissappointed in the results of 2700fps was truly hoping for around 2750 0r above. But it is extremely accurate with this load. </div></div>

While this is true it also means that if you push it to max pressure then you will go through barrels faster. If that is not a concern to you, then by all means push it fast. I personally think you had a slow lot of H4350 and would be curious to see what your speeds are after your revisit load development.

I looked at JBM again and it appears to only be a .2 mil difference in wind between 2700 and 2800 or 7.2" at 1k.

 

[Rob01]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: blklabs</div><div class="ubbcode-body"> I personally think you had a slow lot of H4350 and would be curious to see what your speeds are after your revisit load development.

</div></div>

He is using IMR4350 now and will be switching to H4350, which is a good move. He should have no problem getting near 2800fps with it.

I have not found H4350 to be inconsistent from lot to lot. No need to adjust more than a couple tenths of a grain.

 

[25MAN]

Re: Is an average of 2700 fps good?

Rob01,

Does H4350 burn that much hotter or is it because my IMR is older that you feel I will gain that velocity switching?

I have 50 rounds loaded and hope to try it out Thursday and I will let you all know, but man I hope you are right.

Hopefully it will stay with in the same accuracy node that I have figured out so I will not have to start from scratch with load development.

You have me excited to see what it will do.

 

[sandwarrior]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 25MAN</div><div class="ubbcode-body">
Sandwarrior,

What length barrel was your buddy running and what type of velocities?
</div></div> He was running a 6.5 Creedmoor, actually two of them about the same. 28" barrel. It seemed to me he was using Varget for powder, if not some flavor of 4350.

He pushes his 123 Lapua's to 2950.

One of his rifles was a Rem 700 Custom and the other was a Surgeon.

 

[Jaxdialation]

Re: Is an average of 2700 fps good?

I use 42g of H4350 with a 142 SMK Velocity is 2780
This is with a 26" with 8 twist.

Im happy with that velocity. I'd be happy with 2700 too.

 

[25MAN]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jAXDIALATION</div><div class="ubbcode-body">I use 42g of H4350 with a 142 SMK Velocity is 2780
This is with a 26" with 8 twist.

Im happy with that velocity. I'd be happy with 2700 too. </div></div>

at first yes I was unhappy with the reults becuase I felt like I should have been closer to 2800fps with that load, but after hearing from people here, I realized its not so bad...so I can live with it. But knowing that I have a chance to get the velocities I originally expected switching my old IMR out for the Hogdons, excites me to try it out...if it doesn't improve then I will blame it on the barrel not having a good bore...

Even factory ammo with the 142 SMKs are estimating 2770 out of a 24 inch barrel...so I know something is up and trying to figure it out.

 

[25MAN]

Re: Is an average of 2700 fps good?

What a difference the H4350 made!!!!

Ten shot string of 43 grains of H4350 and 142SMKs with an OAL of 2.834 was much better velocity wise and I may have gained some accuracy as well

Here is what the velocities read in order:
2828
2819
2828
2834
2829
2839
2813
2828
2841
2855 (scewed my numbers and will remove for settign the range card)

the group measured .356 MOA at 100yds

ES was 42 with the the 2855FPS round and 28 ES without it
SD was 11.6 but again would be less without that 1 high velocity round.
Average velocity was 2831fps! that is a 131fps gain!

I have zero pressure signs, but with the results today, I am extremely happy and putting a done stamp on this project and not playing with the load any longer!

I appreciate everyone's input and felt I would share the results from today.

 

[0481]

Re: Is an average of 2700 fps good?

Glad it worked out for you. Now go shoot it.

 

[VKC]

Re: Is an average of 2700 fps good?

that is close to what factory hornandy 6.5 creedmoor is loaded at, interesting. seems like 6.5 creedmoor and 260 rem like that powder and about that velocity.

 

[mbandy13]

Re: Is an average of 2700 fps good?

I would work with that load some more, and get your numbers down even farther, I would play with the seating depth. Im not done with my loads until they are S/D of 3 or less. Good luck to ya.
mike

 

[25MAN]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mbandy13</div><div class="ubbcode-body">I would work with that load some more, and get your numbers down even farther, I would play with the seating depth. Im not done with my loads until they are S/D of 3 or less. Good luck to ya.
mike </div></div>

yeah...i would like to cut down on that and I think I will start going off the ogive instead of the OAL and hoping that will lower my SD.

Great point and was thinking i needed to lower that after I made my last post.

 

[mbandy13]

Re: Is an average of 2700 fps good?

I only work off the ogive I also make sure that all the bullets Im using measure same from base of bullet to ogive as well.

mike

 

[25MAN]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mbandy13</div><div class="ubbcode-body">I only work off the ogive I also make sure that all the bullets Im using measure same from base of bullet to ogive as well.

mike </div></div>

Not sure if you use SMk 142s but do you usually find a big variation? or better worded...what varition do you except as I am assuming not all will be perfectly matched.

Thanks for the advice and help.

 

[Centerfire1]

Re: Is an average of 2700 fps good?

YEP !!! What Mike said.
Where have you heard that before 25MAN??

 

[25MAN]

Re: Is an average of 2700 fps good?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Centerfire1</div><div class="ubbcode-body">YEP !!! What Mike said.
Where have you heard that before 25MAN?? </div></div>

First time I have heard this actually...oh wait maybe once before...haha

 

[mbandy13]

Re: Is an average of 2700 fps good?

It all depends on the luck of the draw with sierra, some boxes are very good other times you might have a few different bullets in the same box of 500. I usually will take bullets that are within .001 off the number. other than that they get seperated into to groups of there own. I find that the 139gr senars tend to be very consistant within the box.

mike

 

[dar1246]

Re: Is an average of 2700 fps good?

Try going to H4831SC powder. One of my last 260s did the same thing. You will get more speed with less pressure.

 

[25MAN]

Re: Is an average of 2700 fps good?

I am also hearing RL17 may be the way to go