190gn and up in .300win mag?

[EXPRESS]

I'm preparing a load for hunting ibex in Kyrgyzstan in 3 weeks time.
The 220SMK, 200SMK, 190SMK, are the pool of hevier bullets I have to choose from. I only have IMR4895, VV N160 and VVN560 to use as powders.

I wasn't able to find much info on these weights for loads, so I'd like to hear what people have found works best out to the 800 yard mark. Can I get away with a 180gn bullet for these kinds of distances?

Any advice would be appreaciated, tomorrow I will shoot the first batch of 220grainers and see if they prefer one specific powder, if the 220gn SMK's wont shoot then I'll start looking at the lighter choices. I'm running a Shilen select match grade barrel, 1:10 twist, so it should stabilize, 26" long on a trued Remington 700 action out of a Manners stock.

Thanks.

 

[trueblue]

Of the 3 powders you listed, I would start with the N560. I think it would give you the best velocity with the least pressure of the 3.
For the 190-200gr SMK you should be around 75-80gr of N560
For the 220SMK you should be 70-75gr N560.
Would up and check your pressures.

 

[EXPRESS]

Well after todays session, I found that the 220gn SMK's shoot just so fine that I have settled on the bullet.

A load of 62.6gn of VV N560 gave 2550fps and a group of .38MOA.
Next in line was VV N560 with 65.5gn and that shot .8MOA at 2650fps.
This was just preliminary testing but I think there is very little to play with here. I am pretty sure that I can get the 220SMK to about 2800/2750fps since there are no pressure signs yet.
VV N160 was right on MOA, IMR4895 was all over the place.
Was shooting at 300 meters, breeze up to 8mph at times.
I might do a ladder shoot tomorrow or just make up some 3 shot batches to see where the sweet spot is, if I can find another one closer to 2800.
What kinds of speeds are people getting with the 220grainers in .300wim mag?

I honestly can't see a problem with terminal ballistics using the 220gn SMK on ibex, there is just so much lead and SD there that even if it does start to come apart there will still be a big chunk there to carry on. With a BC of .629 it's going to be wicked shooting through the wind, and I prefer to compensate more more drop than dope more wind.

Things look good, and I've got plenty of free time to dedicate to shooting before I go, only real hassle is that it's almost unseasonably hot here now, which means long pauses between shots and higher pressures compared to what I will get in Kyrgyzstan.
I spent the evening preparing 100 pieces of new brass, tomorrow I'll shoot some more and start to experiment the drop at the longer ranges.

 

[liltank]

Sounds like you have yourself a winner of a load. Good luck on your hunt.

Tank