The 6mmBR, 6mmBRX, 6mmDasher, 243Winchester, 6mm X 47, 6mmXC, 6.5 Creedmoor, 260Remington, 6.5 X .284, 7mm08, 7mmBR, .284Winchester, 30BR, 308Winchester all provide an excellent platforms from 100 to 600 yards.
I shoot necked up 243 Lapua and necked down Win 7-08 brass. They both shoot extremely well in my rifle. The Winchester brass last 4-5 reloads before primer pockets loosen too much to use. Have loaded the 243 brass only 3 times pockets are still tight. 243 Lapua brass requires neck turning to remove the doughnut. 7-08 is pass through the 260 die and regular brass prep and load.
I build for my customers and personally shoot a 6mmBRX. It has the following characteristics:
Parent cartridge 6mmBR Great inheret accuracy, low recoil, Lapua Brass, Berger or Sierra Bullets. Small Rifle primers, works well with Varget, Reloader 15, H-4350, VV550. Shoots within inches of a 6.5 X .284 at a 1000 yrds. Can be loaded with standard 6mmBR dies. Fire form loads accuarte enough for 600 yard matches. You can buy 200 rounds of Lapua brass and it can be reloaded 15-20 times. The entire life of the barrel. It is a win wnin cartridge no puns intended. If you build one for your wife you will like it so much you will start shooting one too.
This will be for prone. But like I said before this is for fun and our enjoyment the competition is secondary. We are new to this and just want to have fun as a family, we love to shoot and I enjoy the thought of more practice at longer ranges. Its getting so hard to find a place locally to shoot without driving hours. I notice you mention Washington, I see tri-cities has a 300/600 yd prone events. Do you have any info about them?
my wife said she wanted to go hunting and shooting with me and for me to find he a rifle that she could shoot and i looked at .223, 25-06, .243, 6mm, .270, .308, and even a 300w.mag and she liked my .270 the most since my dad and i built it i couldnt afford to buid her one and i bought a rem. 700 with 24 inch barrel and stock it kicked the *&^% out of me so i had the stock cut 1.75 inches and had a sholder saver pad mounted then had the barrel floated and a 3.5 inch long muzzle break fitted and for a rifle that cost me $600.00 i put in $300.00 the first time we took it out she said that it looked like a sniper rifle and was realy intimidated by the look of it but i explained what every part and mod was and how it benefits the shooter this is one girl that at 600 yard is deadly
ps. due to hers having a 24 inch barrel and mine having a 26 in bull barrel the hand loads are different even though "there both .270's" and she realy likes the 90 grain barnes with A.A 2520 @ 50.2 its alittle faster that my 130 grain nozzlers with imr 4350 @54.4 but there just as accurate and it gives me lots of time at my bench loading and on the bench shooting right next to her.
i also am always looking for a new toy and the .22-250 that i had was awsome for anyone to shoot concistently also the .223 swift they just didnt have the take down power off the range that she needs for elk in idaho.
have fun shopping.