Advanced Marksmanship Does your rifle shoot like this with 75gr? PIC

[finbox]

Hello,

Does anybody else have a huge down and right shift when shooting 75gr bullets?

I compete in three gun matches and practice with 55gr and 62 gr, but on the longer distance ( 250-500 yards). I like to run 75gr. Sometimes I don't know the COF until the walk though so zeroing the rifle for the 75gr, if its a 200 yard plus stage is impossible.

I can't afford to shot 75gr match all the time.

Pic is a 100 yard target, scope is a Bushnell 1-6.5
I can understand a vertical shift but the right shift makes it all but impossible to use 75gr without a complete rezero of the scope.

 

[Silent]

Re: Does your rifle shoot like this with 75gr? PIC

How does the 55gr / 62 gr perform at that distance? 250-500? If it performs the same / comparable I would just use the 55gr / 62. Type of rifle and barrel specs? Length, twist etc? Is the shift repeatable or does it change?

 

[finbox]

Re: Does your rifle shoot like this with 75gr? PIC

75gr is WAY better at longer ranges...that's why I want to use it.

Larue predatar 1/8 twist 16"

Shift is the same with all 75gr ammo, PPU, FGMM, TAP etc

 

[jpretle]

Re: Does your rifle shoot like this with 75gr? PIC

How about zeroing for the 75g used in competition and accepting the practice loadings for what they are????

 

[flounderv2]

Re: Does your rifle shoot like this with 75gr? PIC

Not trying to be mean or anything but I would go back to the loading bench because I sure wouldn't be happy with either of those groupings.

Start fresh, find something that works and stick with it for both ranges. If you cant afford an extra few bucks for the 75, then maybe stick with the 62 or 77SMK which is perfectly capable at the distances you mentioned. You're awful worried about accuracy at distance but if those are your groups up close, then you need to rethink your argument because those groups are nothing special IMO.

 

[bmt]

Re: Does your rifle shoot like this with 75gr? PIC

FWIW:

My 1 in 8 tikka does the same thing with the Hornady 75s.

SMK 77s do better . . . . .

BMT

 

[finbox]

Re: Does your rifle shoot like this with 75gr? PIC

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: flounderv2</div><div class="ubbcode-body">Not trying to be mean or anything but I would go back to the loading bench because I sure wouldn't be happy with either of those groupings.

Start fresh, find something that works and stick with it for both ranges. If you cant afford an extra few bucks for the 75, then maybe stick with the 62 or 77SMK which is perfectly capable at the distances you mentioned. You're awful worried about accuracy at distance but if those are your groups up close, then you need to rethink your argument because those groups are nothing special IMO. </div></div>

It's only a 6x scope with no crosshairs and a 1 moa dot, (rectical looks like a eotech)was shot off a barricade.

This is a 3 gun setup= speed,speed,speed. And these groups are fine for that purpose.

With my 6-24 scope it shot .510 groups with bipod and bag, but this is a comp gun not a sit at a bench and get great groups setup.

 

[finbox]

Re: Does your rifle shoot like this with 75gr? PIC

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

My 1 in 8 tikka does the same thing with the Hornady 75s.

SMK 77s do better . . . . .

BMT </div></div>

Thanks I will give them a try

 

[flounderv2]

Re: Does your rifle shoot like this with 75gr? PIC

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: finbox</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: flounderv2</div><div class="ubbcode-body">Not trying to be mean or anything but I would go back to the loading bench because I sure wouldn't be happy with either of those groupings.

Start fresh, find something that works and stick with it for both ranges. If you cant afford an extra few bucks for the 75, then maybe stick with the 62 or 77SMK which is perfectly capable at the distances you mentioned. You're awful worried about accuracy at distance but if those are your groups up close, then you need to rethink your argument because those groups are nothing special IMO. </div></div>

It's only a 6x scope with no crosshairs and a 1 moa dot, (rectical looks like a eotech)was shot off a barricade.

This is a 3 gun setup= speed,speed,speed. And these groups are fine for that purpose.

With my 6-24 scope it shot .510 groups with bipod and bag, but this is a comp gun not a sit at a bench and get great groups setup. </div></div>

Doesnt really make sense to me to try and judge your groups by shooting off an platform that is not optimal for judging load performance. If your gun doesnt like the 75 (which it doesnt appear to) then ditch them. No need to fight it when there are plenty of other options available to you. If the 62 or 77smk work for you then go with them. If you dont want to pony up the extra cash, then that is something you have to learn to live with.

 

[finbox]

Re: Does your rifle shoot like this with 75gr? PIC

It shoots the 75gr the best ( .51 groups with 6x24 scope and bags.) it's the shift that's the problem

All the groups above will be a lot tighter IF I was shooting for groups, but the only picture I had was the one above that was shot off a barricade.

Once again group size is not my concern this rifle is very accurate, HUGE shift from 62gr to 75gr is

 

[Driftwood]

Re: Does your rifle shoot like this with 75gr? PIC

How repeatable is your scope adjustment? If you can trust your scope, all you need to do is record the difference and then adjust accordingly. You could zero for either round and then adjust for the other, depending on which one targets have the most room for error. I would definitely try it in practice before attempting it in competition.

 

[9H_Cracka]

Re: Does your rifle shoot like this with 75gr? PIC

Simple answer - it is Spin Drift. Pickup a 2 litre bottle of Spin-D before your next session, drink 12-14 oz over ice, and it will go away.

 

[Mudcat-NC]

Re: Does your rifle shoot like this with 75gr? PIC

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: _9H_Cracka</div><div class="ubbcode-body">Simple answer - it is Spin Drift. Pickup a 2 litre bottle of Spin-D before your next session, drink 12-14 oz over ice, and it will go away. </div></div>

I think you are better off if you skip the ice though.....unless you are shooting bullets at over 3000fps, then ice is fine.

 

[seanh]

Re: Does your rifle shoot like this with 75gr? PIC

Am I understanding that you want to be able to shoot different weight bullets and are expecting little impact change?

If I'm understanding correctly, you're expectation is unrealistic. If you want to shoot 75grn, then sight in and shoot it.

Back when I was shooting different bullets I simply kept a notebook with notes on different click changes at different ranges...may want to try it.

 

[ajwcotton]

Re: Does your rifle shoot like this with 75gr? PIC

It looks to be about 5 MOA right If your gonna shoot the 75 grain stuff dial 5 minutes left and drive on.

 

[BIRDHUNTER]

I would try 69gr SMK. But to be honest I agree with one of the posters above, there is no reason the 62gr won't work for all. Wind will be a little more of a factor but that can be accounted for. If you can afford it I would be inclined to shoot 69gr or 75gr for all cases. Right now you are shooting three different bullets at three different speeds. Remember barrel harmonics and think about the effects!

 

[jeep505090]

Shoot one bullet problem solved. I have a slight POI shift with my JP 1:8 from 55gr to 75gr, so yes to original question. However I shoot the 55gr bullets at every distance, had no problem last year with either first or second round hits at the FNH WV match . Unless your targets are the size of those dots then dont worry about shooting the heavier bullets. If your rifle shoots well with the lighter bullet wieght reliably, learn to read the wind. Most 3 gun targets at distance are not that small to begin with.

 

[Sterling Shooter]

OP,

Use your brain instead of attempting to get answers from others thinking about it for you. Begin by thinking about this fact: the bullet will always go in the direction the barrel is pointed. Being awakened to this fact will lead you to understand where a bullet goes is mostly about maintaining aim until the bullet clears the bore. The recoil of the 75 and 77 grain bullets is heavy relative to 55 and 62 grain bullets, so even though they come to a shooter's aid for mid range shooting, they also bring along a challenge, keeping recoil resistance consistent shot to shot. Keeping recoil resistance shot to shot is your whole problem. The divergent angle of arc from bore at rest and bore at bullet exit, which you get from inconsistent recoil resistance, means angular error, which will increase with distance. The answer is rebuild and control your position identically shot to shot. Be cognizant for the 5 factors of a steady position and you will see improvement.

One more thing, I've read every post responding to your inquiry, 9H was being caviler with the topic; but nevertheless, I think I understand his position. Some of the answers you got looked like a parade of blind men knocking down lamps at a lighting store. Although sincere, some of the answers you have gotten are indicative of mindsets grounded in gobbledygook rather than the principles of marksmanship. In other words, your solution is not about changing bullets, powder, or sight settings. Your solution is make your contact between the gun and ground consistent shot to shot.

 

[shoot4fun]

First, if you show up at my match with 62 GT you will be sent home. They are really tough on steel targets.
Second, pick the best 55 grain you can find and shoot it. Or start reloading and use 69 gr bullets for matches. Don't try shooting 55 and 75 in same match. Making hits is the big thing here and if you are that far off with 75 gr at 100 yards you will miss by a mile at 400 or more.

 

[nicko]

Just no your dope and have 2 zero's adjust back and fourth

 

[bm11]

First off, to the guys commenting on the accuracy- it looks to be about 1 moa to me, which with a 6x scope should be damn good. The OP pointed out multiple times that the ammo, with higher magnification as a factor, produces close to .5 moa accuracy.

The solution is simple. Zero for your match ammo, and record the correction to zero with your practice ammo. Keep it on the gun or in your range bag, but if your scope is worth half a shit, you should have no problems dialing back and forth between the two. Problem solved. It's the same concept as anyone who shoots with a suppressor. You either zero with it on or off, and record the correction for the other. Unless of course you are lucky enough to have a suppressor with negligible shift (cough SUREFIRE cough.)

 

[2clicks]

Your scenario is why they make high dollar scopes that track properly. Write down your long range zero's with the 75's and use them. I like to write them on my mags with the appropriate bullets in them that way they are quick to reference.