Range Report Using different loads with the same weapon/zero

[LawnMM]

How much of a difference do you guys see using different loads with the same weapon and zero?

My rifle was zero'ed with 168gr FGMM and its pretty damn dead on with that load. I experience a bit of a shift in impact when switching to southwest's 175's.

I'm gonna preface all this with the knowledge that I'm a total noob to long range shooting so I expect a good deal of the difference (maybe all of it) is my own inconsistency and intermittent distraction that tends to be the norm at this particular range.

I expect my results would be different at a range where I was able to focus more and didn't have to fight vibration on my shooting platform from other shooters. However, it planted the seed in my mind about differences in loads. I think it makes most sense to zero with the load you use most. To this point thats been the 168's for me but as I start moving farther and farther out I plan to use the 175s from southwest more.

Do you guys rezero with different loads or do you do some sort of comparison to determine the differences between the loads when using one zero? This question make sense?

 

[427Cobra]

Re: Using different loads with the same weapon/zero

My 260 shoots 1 inch higher with 130vlds, than it does with 139scenars, so yes if you switch bullets your zero will shift

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Do you just build the difference into your firing solution then? Is the difference constant across different ranges? If you are say half a mil high with an alternate load do you just add that to your dope at whatever range you are shooting at?

 

[azimutha]

Re: Using different loads with the same weapon/zero

It's good that you're asking these questions and this is a good place to start. You might say that with a heavier bullet it's all downhill from there...there being your zero. So, no, if you were half a mil off at 100 you'd just be even more off the farther out you go. That's because generally a heavier bullet is going to start out with a lower muzzle velocity and will drop more. However, a heavier bullet of the same type will also have a higher BC (ballistic coefficient) which will lessen the drop somewhat.

Check out http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi. Try out, for example, a 168 gr. SMK and a 175 gr. SMK (using the Litz versions). Lower the muzzle velocity from 2650 to 2575 and you will see the difference between the two in terms of drop and windage. Note: that's just an example. Muzzle velocities vary from rifle to rifle. Also, as you will see there are plenty of other variables, most notably the atmospheric section, that can impact a trajectory.

 

[vman]

Re: Using different loads with the same weapon/zero

I tend to see a slight change in zero when I change between different loads with the main factor being drop. I havn't really given this too much thought to be honest.

I try to keep my rifle as a "single bullet" system.

You could take notes just as you would with cold bore, and see if theres a pattern that occurs when you keep zero for one bullet, but shoot a different bullet using the pre existing zero.

Perhaps an LEO sharpshooter that uses a two bullet system (for glass breaking) can chime in with their knowledge.

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Makes sense. So the only way to use multiple loads on the same zero would be to work up your own custom drop/windage table with the secondary load.

I bought a case of 168 FGMM a while back that I'm working through and I just picked up some of the Southwest 175s. Since any difference between the loads from the 168s to the 175s will compound in a non-linear fashion over distance I can't really use both. Unless I want to put the time in to create a custom drop table with dope on the 175s using the zero setting for the 168s.

That seems like a pita to me. If you run different loads do you all just get in the habit of zero'ing the rifle at the range when you are setting up for the day with the ammo you plan to use? That seems more practical than building a table for a secondary load so you have the corrections needed to keep the rifle zeroed with the primary load.

 

[BryanLitz]

Re: Using different loads with the same weapon/zero

It's not that bad.

The procedure is to establish a 100 yard zero with your primary loads. Set your scope turrets to zero.

Then, find what scope settings are required to be zeroed with the new ammo. Let's say the scope needs 3/4 MOA up, and 1/4 MOA right to be zeroed with the new ammo. Write that down.

Now any time you're shooting LR with the primary ammo, simply go from zero with your scope turrets. Anytime you use the other ammo, 'pre-set' your turrets to 3/4 up, and 1/4 right and apply any corrections on top of that.

In my experience, I've found the difference in POI to be very unpredictable for different weight bullets. For example, a 300 Win Mag was zeroed at 100 for 175's, and when I shot 240's from it with the same zero, they hit over 6" HIGH at 100 yards. The POI shift isn't totally due to difference in ballistics between the two rounds, but also has a lot to do with barrel harmonics and other launch dynamics. I've had some rifles that had a lateral POI shift with different bullets. It's just something you have to shoot, then write down.

-Bryan

 

[Lindy]

Re: Using different loads with the same weapon/zero

I only dial wind when the correction for it exceeds what I can hold on the reticle, so when changing loads, I just dial the windage to the offset and leave it alone.

I do re-zero the elevation turret to the new setting, though, so I don't have to worry about that offset under pressure.

Some ballistic programs, notably Field Firing Solutions, will handle that transparently for you once you set the program up. Then it will give you a turret setting correct for the new load from the zero of the other load.

There is more than one way to skin that cat - just pick a method, and apply it consistently.

 

[CoryT]

Re: Using different loads with the same weapon/zero

Exactly as Bryan says, just reset to zero, or +/- that amount onto the CORRECT DOPE for the round you are using. Both the zero point and the actual elevation for a given range will vary as you change ammo types. As long as you have the proper elevation setting, the only 'error' is the offset from the actual zero setting on the gun.

I actually got Blaine to add this function in Field Firing Solutions software, since there is a need for selecting the correct ammo for a target and it's rather annoying to deal with a number of offsets. The program lets you enter multiple ammo files for a given rifle, each with it's own offset in windage and elevation. Now when it calculates teh setting, it applies the offset and you just read the setting. Also handy for suppressed and unsuppressed zero shifts.

If you only use a couple loads, it's pretty simple to keep track of on the data card. My .338 LM test bed system has 11 loads assigned, I never reset the knobs, just select the ammo and drive on.

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Thats kinda what I was getting at, I must have worded it poorly.

If the primary load is the zero. Maybe I have to add .4 mils of elevation and .2 of windage to get the secondary load dead on. I can use the regular dope for the secondary load I just have to add that offset to any firing solution, right?

So if the dope for a 600 yard shot with the secondary load called for 4.8 mils of elevation, I need to dial that, plus the .4 of elevation shift to 'zero' the secondary load, and add the .2 mils of right or left windage required to move the load to 'zero'

Have I got this correct?

 

[Bearwalk]

Re: Using different loads with the same weapon/zero

Ahhh...but there is a "hard part", or at least a potential "gotcha" and that is remembering which zero you have your scope set for, especially if you reset your turrets each time. You will forget eventually, if you are not careful, and it will happen at the least opportune time. Ask me how I know.

If you are truly going to do this, <span style="font-style: italic">get yourself a scope with zero-stop.</span> Then, set your elevation zero-stop at the "low" zero and <span style="font-style: italic">leave it there</span>. Always. No if's... no but's. You can reset your turrets all you want (more on that in a second), but at least you will always have a baseline to tell you where you are at any given time should you get "lost". In this manner, you will always be able to get back to your low zero quickly.

To find my second (note high) zero quickly, I <span style="font-style: italic">do not reset my turrets when changing loads</span>. I leave the zero stop at the "low" zero, as mentioned, and the turret numeral zero on my "high" zero - if that makes sense. I can then always dial down and find my low zero and then not have to count or calculate for my high zero... just dial up until I have the turret numeral zero at the mark. whew! Harder to describe than do it.

For windage, I use a small drop of different colored paint to mark my different zeros. A bit easier since I have the luxury of walking away if a wind requires more than 12 moa of correction.

If you use my method above, here's how you set up your windage turrets. Dial your windage turret to the setting that corresponds with your "low" zero. Mark with paint. Now dial to the setting that corresponds with your "high" zero. Reset your windage turret. Now, your zero stop (low zero) corresponds with the paint marker and the numeral zeros correspond on both turrets for the "high" zero.

Hope this helps.

 

[Lindy]

Re: Using different loads with the same weapon/zero

Yes.

 

[Graham]

Re: Using different loads with the same weapon/zero

I am fortunate enough to have a secondary load is that has a zero of .3 Mils left of the first load. I never re-adjust the windage knob and I don't dial wind. But problems can happen when I get complacent and check the windage knob to see what load I am using instead of looking at which the ammo is in the box. In flying, the airspeed indicator is the primary instrument for the climb. In shooting, I have to remember that the ammo box is the primary instrument to determine which load I am using.

 

[jbmillard]

Re: Using different loads with the same weapon/zero

This is why some of my calculators have a "zero height" and "zero offset" so that you can account for the differences in zero position on the target for different loads.

Brad

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Ok. Interesting trick with the zero stop. Brad...if I plug in the zero height and offset numbers into the calculator does the output build that in then? In effect adding the offsets and dope together to give you a corrected table for the alternate load? If so...thats pretty slick.

We went shooting yesterday and the tables I brought were garbage they were off and we had to spend 2-3 rounds getting on target at varying ranges. Reading up on wind more (which was our nemesis) and generating some better tables are on my list of homework before the next range session.

Gonna spend some time on the JBM site later today!

 

[Lindy]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">if I plug in the zero height and offset numbers into the calculator does the output build that in then? In effect adding the offsets and dope together to give you a corrected table for the alternate load? If so...thats pretty slick.</div></div>

I'm sure Brad will answer your question - but why don't you try it, and find out?

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Been trying...not finding where to put it. Sorry, I'm just new with the ballistic calculators. I have the values I'm just sifting through the different calculators looking for where to plug this in.

Edited to add - Nevermind I misread the field descriptions, I think I found it.

Double edit - Brad, when punching in the offset for the secondary load, say its 1.2" low and .4" right, you need to modify the original bullet settings correct?

To generate a corrected table for a secondary load, in my case 175 HPBT's, I put in the ballistic coefficient of the round, and the offset from the 168's impact, and that generates a table with that offset built into the table for the 175's then, right? Adding offset information just skews the table for the round by whatever you plug in for those fields if I understand how to do this correctly.

 

[jbmillard]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Double edit - Brad, when punching in the offset for the secondary load, say its 1.2" low and .4" right, you need to modify the original bullet settings correct?

To generate a corrected table for a secondary load, in my case 175 HPBT's, I put in the ballistic coefficient of the round, and the offset from the 168's impact, and that generates a table with that offset built into the table for the 175's then, right? Adding offset information just skews the table for the round by whatever you plug in for those fields if I understand how to do this correctly.</div></div>

Yes, that's correct.

Brad

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Excellent thank you.

 

[one shot ST]

Re: Using different loads with the same weapon/zero

Some pictures to show what Cory and Lindy say

In FFS there are a lot of settings, some are the off sets, you can create a lot of profiles with differents settings, for example in my HTR I use 2 bullets SMK 175 ( primary load ) and Berger VLD 185, with this one I've at 100 m a different POI .1 MIL high and .1 MIL left..... so I create an off set where if I use a Berger bullet automatically I've my POI corrected.

you can do this for bullets, for different shooting position, different light condition, suppressed, unsuppressed..... so every time you got a different POI from the primary.
And off course every thing is also recorded in my log book, in case of PDA failure.

here you can see my primary load, SMK 175 on the lower right hand side on W and E there is no off set

here I've changed my load using a Berger 185 where I've an off set an 100 m

this is the list of my load, with the off set

on the main screen you can manage 4 items T target with the present FFP, R rifle, O off set , B bullet....

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Thats pretty slick. I've been messing with the JBM solution and that works pretty well. Only gripe, if you could call it that, is that the offset can be plugged in with inches or centimeters, but not with MOA/MIL adjustments from your log.

Can you run FFS on regular windows to generate tables to print or is it locked into windows mobile?

 

[one shot ST]

Re: Using different loads with the same weapon/zero

actually there is only the mobile version... but is easy to export in excel a ballistic table, from the PDA...... you can also delete all the columns you don't need.

 

[LawnMM]

Re: Using different loads with the same weapon/zero

Thank you for the info! Still playing with tables trying to get set up in that department.

 

[Notso]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JBM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Double edit - Brad, when punching in the offset for the secondary load, say its 1.2" low and .4" right, you need to modify the original bullet settings correct?

To generate a corrected table for a secondary load, in my case 175 HPBT's, I put in the ballistic coefficient of the round, and the offset from the 168's impact, and that generates a table with that offset built into the table for the 175's then, right? Adding offset information just skews the table for the round by whatever you plug in for those fields if I understand how to do this correctly.</div></div>

Yes, that's correct.

Brad </div></div>

I must be doing something wrong, because I've been palying around with JBM and trying the offset function. My REAL WORLD change from my zero load with 175 SMKs is dead on at 100yds. When I shoot my new 185 Berger LR BTHP, they group about .2mil high and .1mil right. I tried plugging those numbers into every field in that section I could (zero height, zero offset, sight offset, elevation, etc.) and there was no change in the ouput. For instance I was shooting at 640 yds and JBM says 5.2 mils. Actual dope was 5.0, so I thought I could change the offsets for what real world zero with the 185 Bergers were doing. No matter what I changed, the output at the range was still 5.2 mils. What am I doing wrong?

 

[RobertB]

Re: Using different loads with the same weapon/zero

Shoot 1 load. Problem solved.

 

[LawnMM]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JBM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Double edit - Brad, when punching in the offset for the secondary load, say its 1.2" low and .4" right, you need to modify the original bullet settings correct?

To generate a corrected table for a secondary load, in my case 175 HPBT's, I put in the ballistic coefficient of the round, and the offset from the 168's impact, and that generates a table with that offset built into the table for the 175's then, right? Adding offset information just skews the table for the round by whatever you plug in for those fields if I understand how to do this correctly.</div></div>

Yes, that's correct.

Brad </div></div>

I must be doing something wrong, because I've been palying around with JBM and trying the offset function. My REAL WORLD change from my zero load with 175 SMKs is dead on at 100yds. When I shoot my new 185 Berger LR BTHP, they group about .2mil high and .1mil right. I tried plugging those numbers into every field in that section I could (zero height, zero offset, sight offset, elevation, etc.) and there was no change in the ouput. For instance I was shooting at 640 yds and JBM says 5.2 mils. Actual dope was 5.0, so I thought I could change the offsets for what real world zero with the 185 Bergers were doing. No matter what I changed, the output at the range was still 5.2 mils. What am I doing wrong? </div></div>

The zero offset and windage offset are in inches or centimeters. Make sure you plug the offset in with the right unit of measure. If you plug in one centimeter or a tenth of an inch it probably won't make any difference in the generated chart.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">Shoot 1 load. Problem solved. </div></div>

Productive answer, thanks

 

[Notso]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JBM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Double edit - Brad, when punching in the offset for the secondary load, say its 1.2" low and .4" right, you need to modify the original bullet settings correct?

To generate a corrected table for a secondary load, in my case 175 HPBT's, I put in the ballistic coefficient of the round, and the offset from the 168's impact, and that generates a table with that offset built into the table for the 175's then, right? Adding offset information just skews the table for the round by whatever you plug in for those fields if I understand how to do this correctly.</div></div>

Yes, that's correct.

Brad </div></div>

I must be doing something wrong, because I've been playing around with JBM and trying the offset function. My REAL WORLD change from my zero load with 175 SMKs is dead on at 100yds. When I shoot my new 185 Berger LR BTHP, they group about .2mil high and .1mil right. I tried plugging those numbers into every field in that section I could (zero height, zero offset, sight offset, elevation, etc.) and there was no change in the ouput. For instance I was shooting at 640 yds and JBM says 5.2 mils. Actual dope was 5.0, so I thought I could change the offsets for what real world zero with the 185 Bergers were doing. No matter what I changed, the output at the range was still 5.2 mils. What am I doing wrong? </div></div>

The zero offset and windage offset are in inches or centimeters. Make sure you plug the offset in with the right unit of measure. If you plug in one centimeter or a tenth of an inch it probably won't make any difference in the generated chart.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">Shoot 1 load. Problem solved. </div></div>

Productive answer, thanks </div></div>
Yeah, I put in 1 cm into the Zero offset and nothing changed all the way out to 1000 yds. I don't buy that if your zero is off by .1 mil at 100y, it won't be off by an even greater amount at 1k. So I'm still clueless about how this offset thing works.

 

[LawnMM]

Re: Using different loads with the same weapon/zero

If you like PM me or post all the pertinent data and I'll try running it from here. I can print the output to PDF and email it to you.

 

[armymedic.2]

Re: Using different loads with the same weapon/zero

i plugged in 10 inches in the offset and saw no change.......gotta be doing something wrong

 

[jbmillard]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armymedic.2</div><div class="ubbcode-body">i plugged in 10 inches in the offset and saw no change.......gotta be doing something wrong </div></div>

If I plug in 10" for the zero height with a 200 yard zero, I see this:

<div class="ubbcode-block"><div class="ubbcode-header">Code:</div><div class="ubbcode-body ubbcode-pre" ><pre>
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yd) (in) (MOA) (in) (MOA) (ft/s) (none) (ft•lbs)(s) (in) (MOA)
0 -1.8 *** 0.0 *** 3000.0 2.696 3356.7 0.000 0.0 ***
100 6.3 6.0 0.5 0.4 2847.2 2.559 3023.5 0.103 18.1 17.3
200 10.0 4.8 1.9 0.9 2699.6 2.426 2718.2 0.211 37.1 17.7
300 9.0 2.9 4.4 1.4 2556.9 2.298 2438.3 0.325 57.2 18.2
400 2.6 0.6 8.0 1.9 2418.6 2.174 2181.8 0.446 78.4 18.7
500 -9.7 -1.9 12.9 2.5 2284.6 2.053 1946.7 0.573 100.9 19.3
600 -28.7 -4.6 19.1 3.0 2154.8 1.937 1731.8 0.709 124.7 19.8
700 -55.2 -7.5 26.8 3.6 2029.2 1.824 1535.8 0.852 150.0 20.5
800 -90.1 -10.8 36.0 4.3 1908.1 1.715 1357.9 1.004 176.8 21.1
900 -134.6 -14.3 46.9 5.0 1791.7 1.610 1197.3 1.167 205.3 21.8
1000 -189.9 -18.1 59.8 5.7 1680.4 1.510 1053.2 1.340 235.8 22.5
</pre></div></div>

Note that the zero is 10" high. Is this is not what you're seeing, please report it as a bug so that I can check it out.

Brad

 

[LawnMM]

Re: Using different loads with the same weapon/zero

It works fine on my end. I will use it more when I get into handloading.

Brad...any chance of adding Mils/MOA as units of measurement for the offset fields? That way we have a tangible unit of measure that we are already using in the scope reticles to zero the loads. I don't know how big a PITA that would be to do.

Your site is my new favorite ballistic calculator!

 

[jbmillard]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Brad...any chance of adding Mils/MOA as units of measurement for the offset fields? That way we have a tangible unit of measure that we are already using in the scope reticles to zero the loads. I don't know how big a PITA that would be to do.</div></div>

Done. If you have any problems with it, please let me know.

Thanks!

Brad

 

[RobertB]

Re: Using different loads with the same weapon/zero


<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">Shoot 1 load. Problem solved. </div></div>

Productive answer, thanks [/quote] IT's true. Sorry it comes off as I'm being a dick but I used to try to shoot different loads and had the same problem. I still do to a degree but have a few tricks I use to compensate (my method is allready been mentioned on here) but shooting one load is THE BEST way to master your weapon IMHO. My .260 after load development has shot 1750 rnds through it. I only shot 1 load and have no questions on what the bullet does with that gun. My .308. I found the most readily availble accurate load I could from the local vendors and match that load (to the best of my ablilty) so when I handload and when I have to buy factory there is not a difference for me. Same POI for both loads. I have tested them out to 750 yds and they both shoot the same. My best shooting hand load I have gone away from (still keep the data of course) to settle the problem I had when I ran out of handloads and didn't have my re loading tools on me. ( I live on the road 11 months out of the year. Good luck

 

[LawnMM]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JBM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Brad...any chance of adding Mils/MOA as units of measurement for the offset fields? That way we have a tangible unit of measure that we are already using in the scope reticles to zero the loads. I don't know how big a PITA that would be to do.</div></div>

Done. If you have any problems with it, please let me know.

Thanks!

Brad </div></div>

Thats awesome. Just tried it with the main trajectory tables and it works great. Any chance of adding it to the range card calculators? When you get a chance, don't go crazy!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">
IT's true. Sorry it comes off as I'm being a dick but I used to try to shoot different loads and had the same problem. I still do to a degree but have a few tricks I use to compensate (my method is allready been mentioned on here) but shooting one load is THE BEST way to master your weapon IMHO. My .260 after load development has shot 1750 rnds through it. I only shot 1 load and have no questions on what the bullet does with that gun. My .308. I found the most readily availble accurate load I could from the local vendors and match that load (to the best of my ablilty) so when I handload and when I have to buy factory there is not a difference for me. Same POI for both loads. I have tested them out to 750 yds and they both shoot the same. My best shooting hand load I have gone away from (still keep the data of course) to settle the problem I had when I ran out of handloads and didn't have my re loading tools on me. ( I live on the road 11 months out of the year. Good luck </div></div>

I agree one load is best to learn your weapon. Just posing the question for those with multiple loads or who zero on factory and then run handloads. Obviously people do it as there's been quite a bit of discussion here on how. Wasn't trying to get in your ass, just givin' ya the same grief =)

I'm going to be shooting 175s for the foreseeable future. I will probably get into reloading afterwards and at that point this ability will probably be very helpful. I think about stuff like this from time to time and when I have questions I toss em out to see what the responses are.

I envy you with the .260...thought about maybe converting to one of those but I've still got learning and overhead on my .308 to work through.

Rich

 

[jbmillard]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Thats awesome. Just tried it with the main trajectory tables and it works great. Any chance of adding it to the range card calculators? When you get a chance, don't go crazy!
</div></div>

It's done.

Thanks!

Brad

 

[LawnMM]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JBM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LawnMM</div><div class="ubbcode-body">
Thats awesome. Just tried it with the main trajectory tables and it works great. Any chance of adding it to the range card calculators? When you get a chance, don't go crazy!
</div></div>

It's done.

Thanks!

Brad </div></div>

Thanks Brad, thats awesome service! You Rock

 

[RobertB]

Re: Using different loads with the same weapon/zero

The ,308 is where I would want to be if I didn't handload. Good luck with it. In the future a .260 is a bbl change away. Hope everything works out for ya. The different loads use to torment me. Now not so much, it get easier as time goes on.

 

[LawnMM]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">The ,308 is where I would want to be if I didn't handload. Good luck with it. In the future a .260 is a bbl change away. Hope everything works out for ya. The different loads use to torment me. Now not so much, it get easier as time goes on. </div></div>

Like everything, experience is king.

 

[Notso]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JBM</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armymedic.2</div><div class="ubbcode-body">i plugged in 10 inches in the offset and saw no change.......gotta be doing something wrong </div></div>

If I plug in 10" for the zero height with a 200 yard zero, I see this:

<div class="ubbcode-block"><div class="ubbcode-header">Code:</div><div class="ubbcode-body ubbcode-pre" ><pre>
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yd) (in) (MOA) (in) (MOA) (ft/s) (none) (ft•lbs)(s) (in) (MOA)
0 -1.8 *** 0.0 *** 3000.0 2.696 3356.7 0.000 0.0 ***
100 6.3 6.0 0.5 0.4 2847.2 2.559 3023.5 0.103 18.1 17.3
200 10.0 4.8 1.9 0.9 2699.6 2.426 2718.2 0.211 37.1 17.7
300 9.0 2.9 4.4 1.4 2556.9 2.298 2438.3 0.325 57.2 18.2
400 2.6 0.6 8.0 1.9 2418.6 2.174 2181.8 0.446 78.4 18.7
500 -9.7 -1.9 12.9 2.5 2284.6 2.053 1946.7 0.573 100.9 19.3
600 -28.7 -4.6 19.1 3.0 2154.8 1.937 1731.8 0.709 124.7 19.8
700 -55.2 -7.5 26.8 3.6 2029.2 1.824 1535.8 0.852 150.0 20.5
800 -90.1 -10.8 36.0 4.3 1908.1 1.715 1357.9 1.004 176.8 21.1
900 -134.6 -14.3 46.9 5.0 1791.7 1.610 1197.3 1.167 205.3 21.8
1000 -189.9 -18.1 59.8 5.7 1680.4 1.510 1053.2 1.340 235.8 22.5
</pre></div></div>

Note that the zero is 10" high. Is this is not what you're seeing, please report it as a bug so that I can check it out.

Brad
</div></div>

Ahhhh, that makes sense. It works now. I was trying to plug my numbers into one of the offset fields instead of the zero height. What do all the offset fields do? The "?" definition Links are not very clear as to what they do.

 

[Notso]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RobertB</div><div class="ubbcode-body">
IT's true. Sorry it comes off as I'm being a dick but I used to try to shoot different loads and had the same problem. I still do to a degree but have a few tricks I use to compensate (my method is allready been mentioned on here) but shooting one load is THE BEST way to master your weapon IMHO. My .260 after load development has shot 1750 rnds through it. I only shot 1 load and have no questions on what the bullet does with that gun. My .308. I found the most readily availble accurate load I could from the local vendors and match that load (to the best of my ablilty) so when I handload and when I have to buy factory there is not a difference for me. Same POI for both loads. I have tested them out to 750 yds and they both shoot the same. My best shooting hand load I have gone away from (still keep the data of course) to settle the problem I had when I ran out of handloads and didn't have my re loading tools on me. ( I live on the road 11 months out of the year. Good luck </div></div>
My ultimate goal is to get to the point where I shoot only one load. However there are a lot of reasons why thats unrealistic for many. In my case, when I started back into hand loading for the .308, I bought lots of different bullets, brass and powders to see what my gun liked. In hindsight, that was probably not the best way to approach it, but it is what is is. So I finally settled on 175SMKs with Varget in Lapua brass. But I have a hot 1k load that shoots lights out, but It will give me decreased brass life if I shoot it for everything. So I have a slightly backed off load that I use for tac matches and such. In addition, I have some good loads using Win brass and 168 AMAX and 168 SMKs. I use that for training and drills so I'm not using up my Lapua brass and 175s. I'll do this until I burn through about 1000 of these 168s I have.

So while shooting one load for everything is the ultimate goal, there are legit reasons for having multiple loads.

 

[LawnMM]

Re: Using different loads with the same weapon/zero

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body">So while shooting one load for everything is the ultimate goal, there are legit reasons for having multiple loads. </div></div>

I agree. Notso is doing what I'm going to be doing in a few months as I start developing a handload for my .308

Once you figure out what your rifle likes, then its easier to mass produce practice rounds. I like notso's idea for loading up some good stuff for matches but ease off the recipe a bit for practice loads to preserve brass life. I believe thats why this discussion has generated some interest.

Big praise to Brad for adding units of measure for us same day as the requests. Thats just plain awesome. JBM is great!