Accuracy of high velocity varmit loads

[gamestalker]

I load a lot of light weight varmit bullets for my 270's and 7mm RM mag.s and have always been amazed at the incredible accuracy these light fast flyers are. The other day I took several boxes of 100 gr. Sierra'a and 110 Gr. Speer TNT's to the range. These puppies were loaded with RL22 just a bit over mid rane data. The Sierra 100 grainer's were doing aorund 3400 fps and some change and grouped from .620" - the .700' ish on the wider end at 200 yds. The 110 gr. Speer TNT was in the upper 3300 fps range and was printing just around .500" - .665" range.
One thing I've noticed over the years of loading light weight varmit bullets for the .270 and 7mm RM is when I drop my load down to below mid range the groups open up and produce serious flyer's @ 200 yds., some even 3" - 4" outside the primary group. I also think that shooting lighter bullets has an effect on how well I'm shooting, I think this is due much to the reduced recoil in comparison to the heavier 140-145 gr. bullets.
The 90 gr. Sierra's for the .270 are in the 3700 fps range, and still hold tight .500"-.650" groups. All the years I've been loading hot light bullets I keep hearing how poor my accuracy must be at those velocities, but even I've been surprised in this way.

 

[kingmt]

"I also think that shooting lighter bullets has an effect on how well I'm shooting, I think this is due much to the reduced recoil in comparison to the heavier 140-145 gr. bullets."

Let me put you behind my 30-06 with a 165gr then then switch you to 105gr with the same powder. If you can shoot 20 of them in under a hour I'll buy you lunch.

 

[Walkalong]

There is more than one "sweet spot" velocity wise. You found one at high speed, and when you dropped arbitrarily it accuracy suffered. If you drop it a little at a time, you will find another "sweet spot".

 

[gamestalker]

"Let me put you behind my 30-06 with 165 gr. then put you behind 105 gr. with the same powder"

Where do you want to go eat?
I've loaded plenty of 165's & 180's for my 30-06 with IMR-4350, 7mm RM with 162 gr. and so on, you get the idea. But that was back when I was much younger and didn't mind the recoil as much as I do now. Even the .270 with stout charge of RL19 and 130 gr. bullets is punishing for me to get behind these days. I feel like someone has worked me over after 20 rounds.

"There is more than one sweet spot velocity wise"

Indeed there is, I'm only generalizing my most recent loading experiences. But this is one of the reasons a lot of use enjoy reloading in the first place. We just love trying different loads at different distances, it's what I consider the hobby element of reloading.

 

[kingmt]

It isn't the 165gr that will get you they just warm you up so the 105gr don't whip you on the first shoot.

 

[627PCFan]

I think its interesting that you are getting that velocity with such light grain bullets in 7mm with a slow powder like RL-22. Id be curious what happens when you switch to something like IMR 4831 which has a little bit faster burn rate-

 

[LoonWulf]

I think i know where Kingmt was going with that. I used to use some 120 hornadys in my 7mm remington magnum (lightest ive ever used out of that chambering). They shot great, but when the charge was topped out it actually felt nastier then shooting the 139-154s i normally used. The heavier bullets left bruises (crappy savage 110e balsa wood stock), the light ones stung.

 

[kingmt]

The most I was able to bear was 10 rounds & I folded a sweeter to put under my heavy coat after the first one. It hurts just remembering it. First time I remember my shoulder ringing but with pain instead of sound.

 

[gamestalker]

RL22 has been real good to me with those 100 gr. - 145 gr. application. I run the charge just above the mid range most of the time, although I've taken them to above max from time to time just to see what they will do. I've had 100 grainer's break 3800 fps and surprisingly still maintain a fairly decent group, well a 3 or 4 hole group per round at 100 yds.. Yes they begin to deform and break up. The Speer TNT actually stays together quite a bit better than the Sierra 100's do at those extreme velocities.

 

[ranger335v]

"Accuracy of high velocity varmit loads "

There is NO automatic link between accuracy and velocity for any loads.