300 winnie sight-in issues.

[jogar80]

My cousin works at a clinic where the owner is supposedly a hunting fanatic and hunts all over the world. He came back from his last hunt in Canada empty handed and was talking to my cousin about all the problems he's been having with his rifle. He said that him, his friends, and even his guide with 30-plus yrs experience had tried to sight in the scope on his .300 winmag with no success. Apparently, the scope would need adjustment every 2 shots, and they were never able to zero it.

Anyway, my cousin calls me up and asks what i think about it, my first thought is the scope is losing zero. BTW, this is a stainless/synthetic Sako rifle with a Zeiss Conquest scope.. So my cousin tells his boss Im a decent shot and am pretty good at sighting stuff in. The man sends his rifle to me with a box of ammo and 24 hrs to try and fix it because he's going back hunting the next day, lol.

Now, this would be my first time ever shooting a 300winmag, but I kinda knew what to expect with recoil, and sure enough, I was beat to heck when I was done with that box of ammo!! But anyway, my first shots were 6" low and 4" left... WAY off, but grouped well. Made adjustments till it was dead-on, then put the next 10 rounds all in the same 1-1/2"@ 100 yds. I did notice the barrel gets EXTREMELY hot!! I was letting it cool 1 minute between each shot.

So finally, here is my question to you guys.... What do you think is going on here? I don't think the scope would walk every 2 shots on one day, then not walk at all another day, or is that possible? I think MAYBE the guy is flinching, but then how could I explain all his friends AND his guide failing to sight it in? I doubt they could ALL be flinching. My best guess is these guys are shooting very rapidly (confirmed by one of his shooting buddies that was hunting with him) and the barrel got so hot the shot kept shifting and they kept chasing the shot. But 6" and 4" off?!?! Is that even possible from a hot barrel? The hot barrel theory is the one I gave the owner, and he does not believe me. He swears it is the scope that is wrong.

Opinions?

 

[GooseGestapo]

Two thoughts....

1. There is a loose screw somewhere in the mounting system. Take a moment to grasp the scope in one hand, the rifle in another and shake and twist to see if there is any movement. I've seen this many times on heavy recoiling rifles. Even one of my own, a T/C Contender that loosened up the screws on one of the bases. It went from sub-moa to 4moa and unpredictable.

2. The "others" weren't shooting from a bench/solid rest and were jerking the shots around and twisting away on the turrets after every "precious" shot... (not reloaded ammo....$$$).

Send it back after checking the screws and rechecking the zero. Tell them it was "loose nuts" holding the stock.... Usually right every time....

 

[jogar80]

Well, I checked all the mounting and the screws before shooting, everything seemed fine. I already sent the rifle back since I was on a "deadline" and I have not heard back

 

[powder]

I'm with Goose-I clean threads and loc-tite everything before I go to work on zero.

a. It finds bad threads/loose hardware.

b. Eliminates those possibilitties in future.

 

[finnwolf64]

I had the same thing happen to me. Turned out to be a loose scope mount, but it wasn't easily detected, in that the scope didn't seem loose & couldn't be moved with hand pressure. It would move only occasionally under recoil.

 

[Tarvis]

I was having an accuracy issue with an old model 70 in 25-06. I took it to a reputable gun smith to check the action/headspace, first thing he did (after checking the mounts) was put it in a vice and tap on the scope while looking through it to see if something came loose internally. Considering his scope is a zeiss, that may not be the problem, just a thought.

I'm willing to bet it was a flinching problem, good way for him to figure out and fix that problem is a blind-dummy drill. He could put the rifle in a lead sled and shoot it also.

 

[JEB]

my first thought was loose screws, but if you checked that, i would say a combinaton of extreme barrel heat and his friends trying to sight it in without a bench.

 

[adelbridge]

I had a similar situation with my 7mm rem mag. It would hold a zero for about 2 shots and then be 3" off. I went through 2 boxes of ammo and finally got it to settle down. I took the gun out hunting that night and went to adjust the magnification and the dial was stuck. The scope was moving around in the properly torqued rings until it wedged the magnification dial into the rear scope base. When I took the scope off you could see the drag lines in the scope tube and the rings and the scope base was marred pretty good.

 

[rcmodel]

My dentist ruined an antelope hunt with a 7mm Mag pretty much the same way.

When he brought me the gun I found the barrel had so much copper fouling in it you couldn't see the rifling.
It was coming out in strips for two days of cleaning.

Then, I also found the lock ring on the eyepiece of the scope wasn't even touching the rear lens housing.

Every time he shot, the scope eyepiece ended up pointing a different direction!

When I was all done, the rifle grouped under 1 MOA with the remains of his mixed boxes of left-over ammo.

rc

 

[jogar80]

UPDATE:

Well the rifle's owner has been gone forever hunting who-knows-where and I have been waiting all this time to see if the work I did worked for him. While my primary suspect has been flinching, followed by rapid shooting causing an overheated barrel (or both?), I've been waiting for feedback from the owner. Since he swears it's none of what I mentioned to him, I just wanted to see who's right or wrong, lol. Well my cousin calls me yesterday. Say's his boss was back and told him none of what I did or advised worked, so it was obviously the scope or rifle, as he always claimed. So he got rid of it during his hunt and bought a new rifle in .375 H&H with a brand new scope and had it professionally mounted and sighted in. Turns out that combo also went bad in the middle of his hunt and that rifle he bought (no idea which brand/model) sucks.

LOL, imagine that... what are the odds.... lol.

 

[Vern94]

operator error

 

[Skylerbone]

As previously stated a "loose nut" behind the trigger. FWIW my Canadian guide had just traded in to his first ever center fire rifle and had yet to shoot it. He had little appreciation for rifle hunting and what was needed for a well placed shot. Probably how I ended up standing balanced atop the roll cage of his ATV, one foot on each bar. My plan was squeeze the trigger, tuck my head and save the rifle if need be. Neither guide or rich guy are necessarily synonymous with competent.

 

[elktrout]

Great choice.. He goes from a 300 Win mag to a 375 H&H? What did he shoot before his problems all began? Was the 300 a new gun, after he used a milder kicking gun for decades? The answers might be clues to the real problem - the shooter can't handle magnums. No shame, but it does happen.

 

[tahoe2]

magnums = flinching for me

I don't use em in rifles! Nothing against those that do. I shoot 7x57 mauser, 280 Remington, 30-30 Winchester, 300 Savage, 8x57 mauser, & 375 Winchester. But I'm not trying to kill stuff in the next county either. Not a "magnum" in the bunch, but proven killers. any of them will print 1"-2" or 2"-3" @ 100 yards consistently, from field positions even. I do shoot a couple of 41 magnum handguns, and don't seem to have any trouble with them.