.375 Ruger POI shift 270gr vs 300gr

[UncleScuzz]

Howdy folks, long time lurker first time poster. I just recently picked up an original (pre barrel band) Ruger M77 Hawkeye African in 375 Ruger. Was at the range and zeroed my optic (2-7 32mm Vortex, don't hate!) at 100yrd with the 270gr (Hornady factory ammunition spire points) and got the scope somewhat zeroed. I noticed however that when I shoot 300gr bullets (whether it be factory Hornady DGX superperformance or my own handloads which are a Prvi SPRN behind 74 grains of IMR-4350) that my point of impact was about 5 inches low. So my question I suppose, is this a normal POI impact shift with 375 Ruger?

 

[1dirthawker]

@UncleScuzz

i suspect it is a normal shift. different bullet weights, (even same weight and different manufacturers) and powders will regularly make the gun shoot to a different poi.

 

[gillettehunter]

It’s not common to have same point of impact when changing bullets. Pretty decent groups. Good luck
Bruce

 

[375 Ruger Fan]

I normally shoot handloaded 300 gr Swift A-Frames in my 375 Ruger with a 23 inch barrel, getting about 2500 fps. Recently, I have been shooting some 250 Hornady Outfitter with 250 gr GMX, with 2800 fps, and the POI is significantly different.

So yes, POI will likely shift with different weight ammo.

 

[deepwater]

Heavier > slower > lower

 

[375 Ruger Fan]

Heavier > slower > lower

That's deep, @deepwater

 

[deepwater]

375 Ruger Fan,
Hang on. I've just scratched the surface. LOL

 

[UncleScuzz]

Thanks for all the replies and info, this is my first medium bore rifle so anything I can learn about handloading for it is appreciated! Also if anyone has any stock recommendations? Through a lot of research here and elsewhere it seems that these original African models had a tendency to split stocks. Regardless I'll probably work on fine tuning the 300Gr load until more bullets come back to into supply.

 

[UncleScuzz]

Also, if anyone has any 300gr lighter loadings for extended shooting, I'm all ears, Thanks!

 

[bruce moulds]

Heavier > slower > lower

not always.
at extreme ranges it can change again also.
as an aside, my experience with 375 h&h is that the same sight setting and a 300 gn bullet dead on at 100, a 270 gn is about 3" high.
this can be quite useful.
bruce.