I would like to load up some rounds for varmints and I'm new to the whole reloading thing.  Will a 1in8 twist rate barrel be too much for a fragile 40 grain bullet?  Velocities will be up around 3700 fps.  Thanks guys!

Probably.  45 grain (NOT Hornet rated) bullets blow up out of my 1/9" barrel.

btt

Depends entirely on the bullet, you can shred a 50grn Speer TNT if you drive it fast enough out of even a 1:10.

But a Nosler Ballistic Tip or a Hornady Vmax, even 40grainers, not likely.    They are tough enough to stand up to some unreal velocities, a 223Rem even with a 1:7 twist driving them at 3600fps or so isn't likely to blow them to bits.

Not a problem...

John Feamster's book, Black Magic, page 217, Hornady V-Max 40 grain at 3805 FPS from a 1:8" barrel.  Accuracy was excellent, averaging 0.549" .

You don't get such groups from bullets that are coming apart but then again, these were from a Wylde chamber.  NATO chambers are a bit rougher on bullets, especially shorter ones.

I think all in all it depends on the rifle barrel itself.  my 1;8 bbl 26" mini would shred 60gr vmax's at over 3200fps.  I think that the nosler bt's will hold a bit better than the hornady's.  also winchester 45gr jhp's would do 3600fps through the 1.8 with no problems @.75" groups..just stay away from the TNT's and Blitzkings- those are tooooo fragile.

I have no "blow ups" shooting light bullets out of my 1/7 the only thing I noticed was that as I went up in bullet wieght the groups got smaller.

My rifle likes the heavy stuff so that is what I feed it. Black hills and Federal 77 grainers

Thanks for all the great feedback guys.  I am wanting to go on a varmint shoot with a few buddies this summer and I was worried that my .223 just wouldn't cut it out past 400 yards.  Too slow/too much drop.  I was seriously looking at the .204 ruger. WOA makes an AR barrel for it but it runs as much as a bolt gun!  Would really like to have my AR be up to the challenge, and based off of your guys info I think it will do just fine!  Thanks again!

A while back I loaded some 40gr Nosler Ballistic Tips just to see if they'd work in my 1/7ROT Colt barrels. I had read that all sorts of bad things could happen-everything from bullets blowing apart in the barrel, to keyholing, to dogs and cats sleeping together.

I'm happy to report that nothing 'bad' happened at all. The accuracy was nothing to write home about, but that could very well have been caused by something on my end. Keep in mind that I didn't take any time to properly develop this load-I simply cranked up the Dillon 550B and slapped them together.

Disclaimer and corporate CYA: My "research" was not intended to be anything more than a quick and dirty test to see if 40gr projectiles would work in my own 1/7ROT barrels. Your results may vary. Different brands of bullet, a hotter powder charge, jacket construction, jacket thickness, or any number of other factors could yield results far different from what I observed. I am not a scientist, nor do I play one on TV. I did not utilize controlled, repeatable scientific testing protocols, nor do I claim that my testing is a definitive answer to the issue at hand. For all I know the next batch I loaded could have exploded, sending seismic shockwaves to all corners of the globe. These shockwaves could have broken off continent-sized chunks of the polar ice cap and caused the worlds oceans to rise-which could have wiped out human civilization as we know it.

In short, it's quite possible that 40gr bullets could wind up being more cataclysmic than the meteor that wiped out the dinosaurs

Use them at your own peril, my brother.

Quoted: I am wanting to go on a varmint shoot with a few buddies this summer and I was worried that my .223 just wouldn't cut it out past 400 yards.  Too slow/too much drop.

If you know you are gonna be shooting out beyond 400 yards I'd say avoid the 40grn flyweights and go with a 55-60grn bullet.

Your wind drift will be slightly less and trajectorys out past 400 yards will be comparable between the 40grn light weight bullets and the heavier bullets, trajectory begins to fall back into favor for the heavier bullets out beyond 400-500 yards.


A vmax is still gonna be able to make a decent mess at 400-600 yards even if it's a slightly heavier slower 55-60grn pill, they are said to expand reliably down to around 1400fps.

Find out what shoots the most accurately in your rifle before your trip and use that as a deciding factor rather than the "lighter faster" mode of thought.     I usually only break out the 40grn pills for short range vermin inside of 200 yards where the trajectory allows me to mostly be point blank on squirrels.