POI Change With Ammo Change

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BigTb17

New member
Alright guys, this is going to give some idea how little I actually get to shoot. Though I've loved and have been shooting most of my life, I don't get to do it much.

Anyway, I recently got to fire a few rounds through my new rifle (CZ 527 .223). It was a last minute invite I received to a range and I wasn't really prepared, so I was freezing (light jacket, tee-shirt, jeans, worn out sneakers, 15*F with a decent breeze). But I still jumped at the chance to send a few rounds through my new gun.

I got it dialed in at 50 yards in three shots, then moved to 100. Clustered a few rounds right around the bull, looking good (Group wasn't great, probably around an inch or a bit bigger, but I'll take that any day when I'm barely able to feel my fingers or toes, haha).

I had brought several different factory loads to see if anything stood out as great or poor. The first 6-8 shots were with Winchester 55 grn. SP. Just high and right of the bull (maybe a half inch high and a half inch right, but the wind was coming from the left, so I decided not to do any more adjusting for the time being).

I then switched to some Hornady 53 grn. Superformance Varmint. Took a shot and couldn't see where it hit. Took another and still couldn't see it. Hmm. Took two more at a different POI and couldn't see those either. Took two more at yet a different POI and couldn't see any of them. Once everybody was ready to go down-range I decided to go see if I could find any of the hits.

It turns out it was impacting around 2" high and 3-4" right from the previous POI. It was just outside of the main diamond, so the hits blended in with the rest of the backround, making them harder to see. The good news is that in each case (three different sets of two shots) the shots were within 1/4'-1/2 inch of each other. So the round shows promise for consistancy (by that time I was really cold and wasn't focusing on my shots as well as I could have been).

Now, this is only my second center-fire rifle, the first being a .204 Ruger. But I've shot everything I could find locally out of the .204 (.32 grn. to .45 grn. in different brands and types), and never saw a POI change of more than an inch or so at 100 yards between them (factoring out group sizes).

The vertical change didn't suprise me too much, but the several inches of horizontal change at 100 yards surprised me a bit.

I'm not really worried about it. I will shoot more when I can feel my extremities and get a much better feel for what is actually going on. Just curious if a change that drastic is normal. I know different ammo can shoot very different (and I think that 53 grn. Superformance is a pretty hot .223 round), but just wondering if that much of a change is the norm, or is a bit extreme.

Sorry for the long winded post.
 
Quote:by that time I was really cold and wasn't focusing on my shots as well as I could have been. ....Any shooting under those conditions are difficult to analyze...I'm surprised that you were able to keep two rounds within close proximity to each other...

I used to train experienced police officers to shoot in all kinds of conditions, but that was only because we were confronted with them year round...But for training a new officer to shoot, it was a waste of time until they had obtained a degree of mastery over the basics...

In answer to your original question,,,Changing ammo will usually change the point of impact to a degree...I have a .308 that, with factory ammo, gives a wider swing that your .223..The one reason that I prefer to reload...

Consistent shooting boils down to being able to repeat the same action/position each time...If I'm trying to evaluate ammo or a weapon, I try to do that in the most perfect conditions that are on the best weather forecast horizon...Otherwise, it's a waste of ammo and time...
 
Thanks for the reply.

Yeah, I honestly wasn't really figuring on getting a lot of data. The guy I went with was just going to try out his new AR-15 setup and was much more prepared for the cold than I was. I mostly just hung out and chatted. I only fired 15 rounds or so. Just took the opportunity to try out the new gun.

I'm sure I'll get a better idea once it warms up. Just curious if that sounded normal. Considering the wind, the fact that I may not have been fully dialed in yet and all, I'm certainly not going to take anything as hard set fact yet.

Anyway, thanks again.
 
normal, yes.

shooting a different bullet with a different powder in a different case with different primers, at a different velocity, there is NO reason to expect the same point of impact either vertically or horizontally.
 
Yes changing to totally different loads can give way different POI's. I have a few loads that are different bullets and powder that have real close poi's and some that shoot totally different. Many variables come into play. You have to shoot them and see.
 
Same gun with 3 different bullets; 100 grain in the red, 58 grain V-max high, 62 grain copper varmint grenades high and right all from a 243 Win Savage 10 Predator. Pick a bullet & stick with it.
 
Thanks guys. I expected them to shoot different, I was just surprised at how different it hit at "only" 100 yards.

I bought 1 box each of a few different loads that are readily available and resonably priced around here and plan on trying them, picking one I like and buying more.

That's what I did with my .204. I had a round picked out and bought a couple boxes. Now it's nowhere to be found around here or on-line.

Wedgy,
Is that lowest group (the one in the red) a two or three shot group? Just curious.
 
The red group is 2 shots , they were walked up from the two black dots covering the holes. I figured two was enough then went to the other ammo.
 
Yep. I was surprised at how much difference there could be too.
I even see that much of a change just switching powders and using the same 58g V-Max. Both loads produce good groups but quite a bit different POI`s.
 
That is normal rather than unusual. Consider the different weights and shapes of bullets and differences in powders and we should expect it. My greatest variation was 5 inches vertical difference between two .30-06 loads. I was sighted in with a hot 165 grain load and shot a mild 150 grain load. The 150 grain load was exactly 5 inches low.
 
I have had many changes in windage as well as elevation while shooting different weight pullets with powders of different burn rates. My first experience with this was when I bought my first centerfire for varminting. I had a Remington 788 and was shooting factory ammo. When I ran out of the WW I was shooting, I bought a box of Remington ammo. I did not rezero and started missing groundhogs. When I put it on paper I found that the new ammo was shooting low right from the old ammo. Lesson learned.
 


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