I have a ar-15 .223 16" bull barrel
rem 700 in 7mm
of these 3 choices, which one would make the best gun for shooting paper at 400 yards? I plan to reload a hunting round for one. I only have 1 scope right now, thats why I am trying to decide on which to start with.
I would say whichever one your going to hunt with so you get familiar with it. That being said.....
7mm would be flatest shooting and with quality bullets have the highest BC for the longer ranges; however....
I personally would go with the 223 or 243. The reason for this is they are mild recoiling and you can really concentrate on proper form with no flinching while shooting. Less recoil also means you can shoot a lot more before your shoulder gets sore. More rounds, better control = better practice. better practice = more confidence in your shooting abilities. Just my 2 cents worth.
Well you didn't specify what 7mm caliber you are specifically speaking. If it is the 7mm Rem Mag, it would be good for hunting to 400yrds and hard on the shoulder for strictly paper punching unless of course you have a muzzle break. Even with that, multiple round consecutively will be limited to barrel heat and having to let cool down will make target shooting long and frustrating after awhile. Now if you stretch that target out to 700 to 1000 yards then the 7mm Rem Mag has its benefits.
If it is a 7mm-08 then you have something, but I'm guessing the latter. So with that said the 223 would be a great paper puncher and varmint round. It is very capable of taking game to 400yrds but moving into the deer size game, you are starting to limit your self to its potential for a successful harvest. This is an optimum caliber for varmints to the size of coyote at that distance and a little beyond, but not by much IMHO.
So let's look at the 243. You will use 20 grains more powder than the 223, but 20 to 30 grains less than the 7mm Rem Mag. You have bullets that can be shot from 0-400 yards that are very devastating on deer size game, and explosive on varmints to 800yrds. Using an 87 to 107(1:8 twist or less required) grain bullet will both punch paper effectively at 400 yards but out to 1000yrds(100-107grn bullet). The 87 to 95grn bullet will do wonders to anything varmint, paper, and deer to 400yrds. This is just my opinion of course. Not to mention you can save money on reloading and spend about the same as non-military 223 ammo if you have to buy factory ammo.
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If by 7mm, you mean the 7mmRM, then to 400yds there is only an inch or two's difference in trajectory between it and the .243, if that. I zero all my rifles at 300yds and they only drop 7-9 inches at 400yds, depending on the bullet weight and velocity.
You will have more power out to 400yds with the 7mm but also more recoil. Some folks, myself included, tend to start flinching after alot of bench work with a heavy thumper. I can't imagine accuracy being any better but that depends on the rifle, shooter and conditions.
IMO, the .223 with 16" barrel is a no-go for deer size game. Fun to shoot, great for varmints and paper out to 400yds and definately cheaper than the other two.
I have a .243 and a 7Mag (dn .300WM) but I also have my eye set on a 1-9" 22-250. I don't need it, I just want it. Go figure. JohnnyK.
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