50gr bullet drop in rifle zeroed for 55gr?

sbaker10

New member
I have my ar 15 zeroed with 55gr m193. My dad bought a couple boxes of american eagle 50gr varmit tips. All shots will be within 220 yards will a 50gr bullet impact in a noticably different place than a 55gr?
 
Even bullets of the same weight, but different types can have a different POI.

Technically, you should rezero/confirm zero anytime something changes. Alltitude, brand/type of ammo, Ect..
 
How much? Today is The only hunting opportunity for a week. One or two inches wouldn't really matter as I am shooting coyotes
 
When I played (tried different reload I made) with my 22-250, the 50 gr were not dropping but about 7" to the lwft and a good 4" high... at 100 yards !!
 
POI with another bullet (lighter by 5 grains) and powder probably won't be just a vertical difference. Might be high and right or high and left or who knows where. I'd sure check it before I went hunting. That said, at 100 yards the diff probably won't be more than an inch or inch and a half. Double that for 200 and you might be Ok. Maybe. And maybe you'll get to see just how fast those coyotes can accelerate when a near miss happens. They can really get it into high gear. I know....and you can guess why.
 
Like sharkbite say, same bullet weight but different ammo /manufacturer and it will be different. Also the speed of the bullet will be very different and dont really believe what is printed on the box, I chrono my load and some hornady, and I also had 2 boxes of winchester super x, the win was around 3920 fts !!!!! if I recall the box show 3500 or 3600 fts. The problem with a fast "varmint" bullet is that it will make a lot more damage to the fur
 
Fur damage is not really an issue. I'm just concerned about m193 tumbling at 200 yards. But that is the range where the ae might me off also
 
There won't be any notable difference in trajectory. However, different loads often have different points of impact, as noted by others, above.
 
Art is right. Running the data through a ballistic calculator, assuming that the stipulated velocities are accurate for the two different types of ammo, the difference in trajectory POI shift are negligible out to 200 yards.
 
I think it depends a lot on the rifle. Some rifles will shoot bullets of varying weights so close at 100 yards to not matter. At longer ranges heavier bullets are slightly, and predictably lower on the target.

With other rifles small changes can mean big differences down range. I'd always prefer to actually shoot some before hunting to know for sure, but if not possible, then it is not possible. More than likely there won't be enough difference to matter.
 
bullet drop

loic said its only 7 in., omg I would have a heart attack,that much between 50 an55gr,i totally agree 1/2 in. max 1 in. an that's pushing things,i would go back to basics,i would shoot the round you zeroed with and see the poi,then shoot the other round for its poi,if it continues to be of 7 inches I would reload some more,an see where they hit,elimate something here,have you checked your scale against another,i could understand vertical shooting high, horizontal,sure its not you,pulling on trigger
 
The 50gr were factory ammo. Actually when I first try to see what bullet weight my rifle will like the most I bought different brand of 50 & 55 gr ammo. I used a bipod and sand bag for the rear. The smallest grouo was achieved with 55 gr bullets. From there I started reloading 55gr bullet with varget. 10 rounds each starting I think it was 34.8 grains all the way to 36.2 by 0.2 gr increments.
 
There are variables of course. In my ARs, at 200 yards, the 50 gr NBTs print about 1" higher than the 55 gr NBTs which print about .5" higher than the 60 gr NBTs. I see no significant shift other than verticle from 50s to 69s even of different manufacturer. Sure, there are better grouping ones than others, and I only run stainless match grade barrels with Wylde chambers, but I doubt you see much difference.
 
The difference in POI will vary with any change in barrel harmonics. How much? No way to tell, ahead of time. I've had some rifle/load combinations not vary; other times, two or three inches at 100 yards.

What little "consistency" might have existed was generally a bit high and off to one side or the other. I don't recall groups hitting lower...
 
I agree with Art about barrel vibration being the big difference in POI. Whippy barrels, shooting harder-recoil cartridges vibrate with greater amplitude than heavy ones.

I'd hazard a guess that the 55 would shoot within 1 MOA of a 50 grain bullet in a .223 or .22-250 free-floated barrel. My .223 Rem shoots 55 grain factory loads about 1" high and a half-inch left of the 50 grain zero.
 
loic said its only 7 in., omg I would have a heart attack,that much between 50 an55gr,i totally agree 1/2 in. max 1 in. an that's pushing things,i would go back to basics,i would shoot the round you zeroed with and see the poi,then shoot the other round for its poi,if it continues to be of 7 inches I would reload some more,an see where they hit,elimate something here,have you checked your scale against another,i could understand vertical shooting high, horizontal,sure its not you,pulling on trigger

Im working on a load with new to me nosler ballistic tip 55 gr. Here is what I got, im shooting from a ......picnic table which has very small feet and wooble quite a bit (im goung to invest in a good shooting mat). But it still give an idea. I couldn't find those hornady 50gr but I'll keep looking.
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Not related but I shot my ar at 500 yards with 3 different type of ammo this is the best I could do but I need to find a heavier hunting bullet (they were 55gr only, I have a 1-7 twist rate)
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Three different loads, three different group centers. Looks normal to me. And 500 yards? Those are sub-MOA groups, so they look good to me.

Summary: Different loads can have different harmonics, no matter what type of barrel is used. Different harmonics = different points of impact.
 
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