Range Report 175 SMK to 600 and 1000

[head2h2o]

Just want to double check my load and calculations with others.

Load: 175 SMK in 308 Win
45.0 gr Varget
Average chronograph speed was 2733

100 yd zero

JBM says the dope for 600 is 14.7 and 35.6 for 1000.

I will be shooting an F class match at 600 this coming weekend and wanted to make sure that I was on track.

I had a few concerns since my 260 load didn't match up exactly with JBM.
Load: 140 gr SMK over 42.8 gr H4350 with a speed of 2737.

JBM says the drop at 300 yds with a 100yd zero is 4.3. I found it do be 3.75.

Just want to see if the data that ya'll get is consistent with this.

Thanks.

 

[desertHK]

Re: 175 SMK to 600 and 1000

Do you have your scope height entered in correctly for JBM? I find that JBM is very much right one the money, at least for me.

 

[head2h2o]

Re: 175 SMK to 600 and 1000

Changing that did help. Thanks. I will get an exact measurement on that tonight and rerun the numbers, but just playing around with the calculator did seem to improve it and make the numbers more consistent with what I found yesterday.

 

[Lindy]

Re: 175 SMK to 600 and 1000

It doesn't matter much, since F-class matches allow sighters. Believe the bullet.

However, you might find this illuminating, or, at least, entertaining: Sources of Ballistic Program Inaccuracies

 

[ReaperDriver]

Re: 175 SMK to 600 and 1000

You could always go and just shoot at those ranges and get the actual dope before the F-class match. JBM or any other program will get you close, but nothing replaces actual dope at the ranges and conditions you'll be shooting. I'm just saying.....

 

[Rob01]

Re: 175 SMK to 600 and 1000

Always found JBM to be real close, like max .2 mils at 1000 off. Inside 800 it's dead on. Make sure all the data you are putting in is right as if it's not it goes back to the old saying of garbage in, garbage out.

Have you run a tracking test on your scope? Might be the scope not tracking right making the inconsistancies.

 

[flyboy]

Re: 175 SMK to 600 and 1000

Brian Litz numbers for the 175's have always been dead nuts on for me here in Houston. 14.7 sounds about right. Be sure in enter the correct temp and baro. info into the program. Otherwise, I'd be shocked if your not on in two shots. That's about what it takes me. I plan on being there at the match also if nothing else comes up.

 

[SScott]

Re: 175 SMK to 600 and 1000

45 grains of Varget in my 24" barrel give me an average of 2723, using RP brass with CCI primers seated to 2.810.
So I would say your speed is right in there.
SScott

 

[Garvey]

Re: 175 SMK to 600 and 1000

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sunnyside Scott</div><div class="ubbcode-body">45 grains of Varget in my 24" barrel give me an average of 2723, using RP brass with CCI primers seated to 2.810.
So I would say your speed is right in there.
SScott </div></div>

+1

44.8gr of Varget did better in my 24" barrel and it gave me 2713 fps, Win LR primers, seated to 2.835". JDM produced 4.2 MIL for 600 and 10.2 MIL for 1000

 

[head2h2o]

Re: 175 SMK to 600 and 1000

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ReaperDriver</div><div class="ubbcode-body">You could always go and just shoot at those ranges and get the actual dope before the F-class match. JBM or any other program will get you close, but nothing replaces actual dope at the ranges and conditions you'll be shooting. I'm just saying..... </div></div>

Not sure why I didn't think of that . . . . It seems sooooo obvious.

Sarcasm aside, the 1000 yd range we have around here will not let you shoot beyond 300 until you shoot a match and qualify to have access to the longer ranges. Otherwise, I agree, I would have checked my actual dope instead of relying solely on JBM. After this weekend, hopefully, it will be a mute point. Plus I like to hear what others that are more experienced than me have to say.

 

[Leaddog]

Re: 175 SMK to 600 and 1000

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: head2h2o</div><div class="ubbcode-body">

...... the 1000 yd range we have around here will not let you shoot beyond 300 until you shoot a match and qualify to have access to the longer ranges. </div></div>

Although I don't agree that a match performance is necessary, I do think that a shooter should demonstrate competence before shooting beyond 300 yards at a club. He/she should be able to hold at least a minute and a half at 300 and have a good understanding of come-ups before going further out. I've seen too many LR wannabees sling bullets into the never never without regard. This is irresponsible. If you aren't sure what you are doing, seek out an experienced shooter and get it right. This isn't a trial and error business. The internet isn't always your friend. There is alot of flawed information on some forums.

 

[ReaperDriver]

Re: 175 SMK to 600 and 1000

Sorry, wasn't trying to sound like an ass about getting dope. But it always struck me odd when numerous folks around here ask about for dope for or JBM/computer ballistics for known distance targets that they could shoot rather than just going and shooting it. I get the questions when it comes to wanting to tweak data for UKD. But it seriously NEVER occured to me that some clubs would restrict you from shooting at ranges until you demo pro'd at shorter ranges.

And I get that there are idiots out there that just sling lead, but I would think that anyone trying to shoot out to 1000 yds (not your typical shooter) would at least have an <span style="font-style: italic"><span style="font-weight: bold">idea </span></span>about basic ballistic and investigate ways to at least get them in the ballpark. As Rob01 said, JBM should get you within .2 mils with the correct data. But yes, I realize that is giving many folks WAY too much credit. I guess I'm just somewhat spoiled by my private range's "big boy" approach out here.

 

[sniperaviator]

Re: 175 SMK to 600 and 1000

What is the elevation and temperature you are using?
What is the BC you are using (and is it inflated?)
Also, if you shoot, make SURE you have your distances accurate. Otherwise you can be off by quite a bit.

 

[scap99]

Re: 175 SMK to 600 and 1000

Sounds like you and I shoot at the same place.

If it's Juliff, as an alternative to a match, the gentleman that can get you certified is there most every Tuesday and Friday.

 

[DedicatedShooter]

Re: 175 SMK to 600 and 1000

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: head2h2o</div><div class="ubbcode-body">Just want to double check my load and calculations with others.

Load: 175 SMK in 308 Win
45.0 gr Varget
Average chronograph speed was 2733

100 yd zero

JBM says the dope for 600 is 14.7 and 35.6 for 1000.

I will be shooting an F class match at 600 this coming weekend and wanted to make sure that I was on track.

I had a few concerns since my 260 load didn't match up exactly with JBM.
Load: 140 gr SMK over 42.8 gr H4350 with a speed of 2737.

JBM says the drop at 300 yds with a 100yd zero is 4.3. I found it do be 3.75.

Just want to see if the data that ya'll get is consistent with this.

Thanks. </div></div>

Your software is right on the money.

My Rifle: 26" Rem 700 with AICS
My 308 load: 175 SMK over 45.0 gr Varget with a CCI BR2, Lapua Brass, seated to 2.825" coal
MV is: 2714 fps

I shoot at 600yds regularly and the drop is 14.5-14.75 MOA all day.

I recently shot in a 1000yd match at Camp Perry during the last weekend in September and my drop was 35-37.5 MOA depending on the wind and it was a very windy match. Came in third place though!!

Anyways, good luck at the match!!

 

[squirrelsniper]

Re: 175 SMK to 600 and 1000

I've always found JBM to be very close to actual firing with most standard bullets; VLDs require a switch to the G7 drag function for more accurate results though. However, the information you get out is totally dependant on the accuracy of the information you put in. In other words, things like scope height above bore, barometric pressure, muzzle velocity, cant of the rifle, or any other huge number of factors can change the results a bit, sometimes drastically.