Home Forums Hunting & Shooting Hunting Rifles POI question - Win M70, 7x57 Mauser - different weight boolits

First off - I will admit to being a noob when it comes to ballistics and center-fire rifle rounds - hence the dumb question that is about to follow.

Took my new (FN made) M70 in hoary 7x57 Mauser to the range today to sight in the scope and get a feel.

I had factory fodder (no brass available so I'll use this brass to reload). Shot 3 different brands/weights.

Started with Federal blue box 140 gr - dialed the scope in - shot about 20 rounds.
Shot another 20 rounds of S&B 140 grain FMJ - POI was the same as the Federal
Shot 20 rounds of 175 grain Federal round nose - POI was 7-8" low and to the left.

The groups were about the same (1.5"-2" - I shot like $hit today been a while since I've hit the range) but the major shift in POI has me a little confused. As a reference my 30-06 has almost not shift in POI between 150 and 180 grain factory stuff.

My plan for a hunting load is 160 grain TSX over 43 gr of I4350.

So - does my rifle just "like" the lighter boolits? Per the interweb it should have a 1-9.5 twist which "should" like most/all boolit weights.

I'm looking for "yeah that's normal" or "your Winny is a POS and you should get a Montucky", or "here is a solution".

Thoughts?

Thanks

Jeff

I'm not shocked , it's pretty unusual to not see some poi change between such disparate bullet weights. Also some of the 175gr 7x57 loads are pretty light. Remember every rifle is a rule unto itself so now that you are on the paper start working up your 160" gr loads and see how you can improve on your results. You may have to work with oal as well as charge weight etc, While the 7x57 round is a classic frankly I have had 2-3 over the years along with experience with a couple of my friends rifles and while all but one finally found a load that shot pretty well they generally took a little more effort than most other cartridges I've fiddled with. That last statement will probably get me flamed but that's been my experience.

Yeah. By no means is 7/8ths a 'major' shift�..


Your rifle will shoot 160s�don't know if it will be the same POI but what does that matter once a load is settled on?

Not 7/8 of an inch. Seven to eight INCHES. Across the entire target - a miss on something small.



Sorry if my post was unclear. I would never have squawked for 7/8 of an inch.

I hate Winchesters,I hate Mouser hulls...but one can't be too tough on the system,when fed such schit ammo.

Trip the works to a sucker and Montucky.

Thank me later...............

Try bedding the rifle...

I had a pair of Ruger 77s that shot real lousy groups... was about ready to either dump them in the river or rebarrel them...

one last load jumped out at me from an old Hornady Manual...

40 grains of 3031, with a 175 grain RN...

Turned 5 inch groups into 3/4 inch groups...

thought something had to be wrong, so I went home and loaded some more... same results....

Tried the same load with 160 grain bullets, 154s, 150s, 140, 139s, 145s.. ALL gave the same results...1/2 to 3/4 inch groups...

anything else, 3 to 5 inch groups...

sold one of them to a forum member who wanted one for his son..., still have the other, and it still gets fed 40 grains of 3031..... although I later found the rifle likes 140 grain ballistic tips with 44 grains of IMR 4895 or 4064 or RL 15...

go figure...

Paradiddle,

My pushfeed M70 7x57 drops the 175 gr bullets several inches low, and left, also. I would say your rifle is in the normal range. I tried over a dozen bullets of all weights and found my rifle shot better with 140's than either lighter or heavier bullets.

I finally found the most accurate load for my rifle when I tried JB's recommended load for the 140 gr bullets of 48.5 gr of H-4350 at 2800 fps with Nosler Ballistic Tips. I found that the 140 gr Partition also shot very well in my rifle, and to the same point of impact.

That is not always the case even with the same weight bullets. Those are all I shoot now; my Standard Loads for that rifle.

I was willing to settle for whichever bullet weight, if any, that my rifle preferred, light or heavy. Looking for some "modern magic" I did quite a bit of work with the 120 gr TTSX, and several newer powders, but I got better accuracy with 140 gr Ballistic Tips and good, old H-4350..

Try different weight bullets in your rifle and see what it prefers. Don't worry about different points of impact for different bullet weights. Lighter bullets usually hit a couple of inches higher. Some diagonal shift is also not uncommon. Good luck and enjoy that fine rifle.

I should add, that it is possible to play with different loads to get a pair of different bullet weights to hit at the same POI, frequently by reducing the velocity of the lighter bullet load. Seldom worth the effort, but it can be done.

A few rifles will behave like your 30-06, but I think it is more the exception than the rule, in my experience.

Thanks. The rifle is factory bedded just as an FYI.

The FN's bedding is usually pretty good from the factory. I wouldn't be suspect of that or change it unless it's shooting poor groups: IE, inconsistently or larger than 2 moa... From the sounds of it, it's shooting pretty accurately. I'd worry more about working up a good load in the rifle with the bullet it likes and then dialing it in for MPBR or what every you choose for zero and call it a day. If you are like the rest of us, the only time you change bullet weights is when you step up or down in caliber

I read it as 7" to 8"...

FN "bedding" is a joke,as a best case scenario.

It's a squirt of hot melt glue...................

LOL, you've come to the right place.

I wouldn't worry about the POI shift, especially between bullets you're not going to hunt with. Load up your chosen bullet and see how that does out to the maximum distance you'll be shooting.

If it shoots well enough to make you happy, the POI of the other bullets won't matter.