Home Forums Hunting & Shooting Custom Rifles & Wildcats Questioning some old wisdom...............

I had always heard that if a rifle was shot with a tight sling compared to shooting off a rest the point of impact would shift. I was always told ( and said this myself a few times) that the pressure from pulling on the front sling swivel would cause the point of impact to change. Well, I had a customer that had a rifle I had built to call and say that his point of impact would shift about 3 inches when using the sling. Well later I got to thinking, if you pull down or to the side on the sling out front then you must push back an equal amount or the barrel would be pointed at the ground ! Well this called for a little test. I went to the range with my 6.5 and a 300 Win. One has a McMillian and the other has a High-Tech stock. I put each in my machine rest and set the rest up to the same place my hand would be if I were using the sling to shoot. Then I hooked a chain hoist to the front stud and chained the other end to the concrete. Sighted the rifles to shoot dead on a 100 yards. I then put some pressure ( one click) on the hoist and shot a group. No change. One more click. NO change. Moved the hoist to pull almost sideways on the stock. Applied pressure no change. Went back to pulling straight down. No change.Kept cranking on the hoist and shooting groups until I pulled the stud and a big chunk of stock completely off the rifles. The point of impact did not change at all during these two test !!! This makes me wonder if it is the shooter that is causing the impact to change. Maybe the stock doesn't fit right or the scope is the wrong height or something , I am not sure but I am fairly sure stock pressure or lack of wasn't having any affect. Both of these rifles I had full contact bedded the action area and on the High-Tech stock, it had a contact point in the forend. I was just wondering if anyone one else has done any controlled test or experimented with this. Would there be a better way to do this test ?
<br>Charlie Sisk

Charlie,I think you covered it pretty good !
<br>dave

I suppose that anything can happen. Maybe the customer sighted in while resting the rifle way back near the magazine and of course the sling and hand were far forward.
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<br>Lot's of other things could have happend like something coming loose and the rifle and you got blamed.
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<br>I like to shoot my varmint rifles with a sling. I sight them in off sand bags on the bench however but the barrels are heavy ones.
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<br>I may run a test for you this week. It will be good practice anyway.

I think most POI shift,resulting from a sling,is caused from a twisting motion. More of a sideways springing of the barrel channel,that induces side to side pressure upon the barrel.
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<br>POI can also shift,when using a bipod. That especially on a "floated" barrel(that is barely floated),that is housed within a fairly flimsy stock. It is easy to spring the stock upwards,causing vertical stringing.
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<br>So I think much depends upon the integrity of the stock in question,the bedding process used and what is used as a support/field rest(be it a sling,bipod,shooting sticks,etc,etc).
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<br>I would expect the test that you did,to cause lesser degrees of POI shift,as the forend is simply pulled away from the barrel,rather than pushing the barrel itself upwards or sideways.
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<br>Be curious to see how many clicks it took to skew a pre-established POI,when incorporating the front swivel stud and an anchor point that pulled sideways on the stock(45 degree angle or so),as opposed to 90 degrees down.
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<br>Thoughts?..................

Charlie, Stick,
<br>Some wonderful points, but flat out, you have to admit that it takes a stout sucker to pull as hard as a come-along, particularly when shooting...
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<br>Comes back to the indian, not the arrow... to paraphrase someone here about.
<br>art

I've given up using slings, I hated having to replace all those studs I yanked out...........

As a big fan of the shooting sling, I enjoyed your post.
<br> I have noticed a POI shift between the use of the sling, in a field position, and a bench position. On a bedded barrel, it has been as much as 3 inches at 100 yds. Townsend Whelen reported the same thing, years ago.
<br> What I don't know is wether this is the change in shooting positons, or the change in pressure on the barrel, or just what. What I have noticed, just like "Towney" did, that free floated barrels makes this difference much smaller with the positons I use at the bench, and in the field. Depending on one's position, there will be a difference, if even a small one.
<br> Anyway, the bottom line, to me, is practice, and check your zero, from field positions. Assume nothing. All my rifle are individuals. None of them feel, or shoot, the same. E

Sitka,
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<br>My thoughts were that beings Charlie had the means to measure "clicks" upon his test bed,it would be interesting to see how little(or much) it took to skew POI. That,as compared to putting serious pressure on the stud,in his first trials.
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<br>Point being,loooooong before the studs came flying sideways out of the stock,a guy would be seeing radical POI shifts.
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<br>The harmony of a given barreled action's relation to the stock it resides in,can be rather fickle. Harmonics certainly playing a major role. I've some rifles that much prefer to be held onto,for dear life(a heavy hand,so to speak). Others could care less,regardless of how I ride the stock or the postion/rest it is shot from.
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<br>I've went to full length bedding many of my light contoured rifles,as it has proven beneficial in that the POI is a constant,regardless of the manner in which the rifle is used. Meaning I can happily go from the bags,to my back pack,to a bipod or a sling(which I seldom if ever employ,as I'm not very well versed in it's use as a shooting aid).
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<br>To sum up my thoughts on the matter,I definately believe there are rifles that are MUCH more fussy than others,in regards to POI shift.
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<br>Interesting stuff....................
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Then there is the issue of studs mounted on the barrel.
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<br>My guess is that it has alot to do with the position of the shooter varying between the shots. My motto in life has pretty much been this: If its good enough for the Corps, its good enough for me. Hence, slings are used. Some rifles are real pains in the keister, but I find that I almost always shoot better offhand with a sling than without.

Cazador,
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<br>I find little coincidence,that the best field shots I know and run around with,were/are Marines. I'm trying to make myself learn and incorporate the sling,but I'm stubborn,even when dealing with myself(grin)..................

Hey guys:
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<br>I just re-read Charlie's post, and it says he moved the hoist so that it was exerting pressure to the side as well.
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<br>Interested in this discussion as I always carry a shooting sling and I practice with one regularly. I love them.
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<br>Rick

Right there in black and white,just too plain for me to see I guess??!??
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<br>I'm much interested too Rick...................

I have seen it time and time again where guys rest the BARREL on the sand bags or clip a cheap plastic bipod to the end of their barrel and proceed to "TRY" and shoot groups. It is quite commical to see the frustration they experience as the harmonics change along with the barrel heating up. At 200 yards they often miss the target and can't figure out why. Oh, and don't forget the fact that they continue to shoot for half an hour and NEVER let the barrel cool. Interesting test Charlie. Keep the results comming. Flinch

Charlie Sisk,
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<br>For a fast answer call Mo at Master Class Sports in Brookfield, CT 203-775-1013. These guys shoot prone all of the time at medium to very long range with slings.
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<br>You have to practice with a sling. At first the pulse that you see with a scope will be disconcerning. I think that most of us old marksmen have so much confidence in the sling as I shot with iron sights so much and saw the results on the target.

All this talk about slings... boy do I feel dumb...
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<br>i was at the range today and was shooting my garand off hand, needing the practice. I had purchased a shooting sling for said rifle and guess what. Of all the ammo I burned up today I did not use the sling one time! I could kick my self. Well I am going back tomorrow and USE the sling and try some of this Wolf steel cased 30-06 ammo. Only difficulty I see with it so far is that I cannot get 8 bullets in the en-bloc. Six or 7 fit fine but the 8the don't work...

Great now I have to hook up a chain hoist on my rifle, oh well I guess it will soften the recoil of my 375 H&H. I always thought a sling was good enough, well now I learned something new.

Thanks for doing the test Charlie. Perhaps you can answer a question for me, though? Why didn't the increase in tension on the stock cause the bullet to exit the barrel differently? I always thought that the bullet is still in the barrel during recoil and different tension on the stock would effect where and how the bullet exiited the end of the barrel. What are your theories, Charlie? Perhaps Ken Howell would also like to chime in on this and help those of us who wonder about such things?

Here is one result as promised. I fired three shots from my M-70 circa 1962 .300 H&H at 100 yards in good conditions from a rest. The group was 1.003" as expected. Then I fired three shots from prone using a marksmans sling. The group was .743" and centered 5/8" of an inch left of the other group that was fired from a forend rest.
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<br>The bullet is the 165 Gr Sierra SBT with a load one grain less than max. This is the standard load for this rifle and I have shot it all year.
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<br>This is only one rifle. These M-70's have a 26" bbl that not all that heavy with a screw into the barrel at the sight boss. This rifle is 100% stock. I could imagine that a different rifle might or miught not have other points of impact.
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<br>I hunt with a heavy barreled .219 K Zipper and I use the sling for long shots and it's always on. But again that is that particular rifle.

Charlie, remind me to never send a rifle back to you for testing.
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<br>Jeff