Loading 55gr Nosler BT Varmint .243

[blzeye]

If you read my last post, you'll see I just got this Ruger & am trying to work thru a few issues. I want to have a varmint load, as well as a good long-range load. As I was measuring for max COL on the different bullets I have, I realized that there's no way I can load the 55gr anywhere close to the lands. There was hardly any bullet in the shell when I pulled out my Hornady bullet comparator. I could hardly even measure it as I had to hold the bullet from falling out of the shell. When I made up a load, the ogive was .125 from the lands w/ the bullet about 2/3 of the way in the neck. Then when I shot it, the velocity was much lower than the book said. I should've seen about 3800-3900 fps, but it was around 3500. The test barrel was 2" longer than mine, so I figured I would lose 100-200 fps, which I accounted for. Anyone have any experience w/ these little bullets in the .243? Thanks!

 

[788Ham]

What is your COL? You didn't post it in your thread. In my Hornady 7th edition, it only shows 58 gr. bullets, the COL in it shows "2.600".

 

[blzeye]

Hornady has the 58gr, Nosler has the 55gr, but I suppose the loads are very similar. I didn't check the COL as I was measuring at the ogive so I could see how far off the lands the bullet is.

 

[helotaxi]

Nowhere near the lands on my Savage .243 shooting any of the 55-58gn pills and it hasn't affected accuracy in the slightest. Those short little bullets aren't all that sensitive to jump since they're less likely to yaw between the case and the rifling anyway.

 

[blzeye]

And could I be losing speed because the bullet has pretty much exited the shell as it hits the lands? Or would I see signs in the chamber if that were so?
I'll load up some more & continue testing. This gun may not like these bullets. It has a 1 in 9 twist. As long as I find something it likes, that's all I really care about.

 

[helotaxi]

I was shooting them and reliably hitting 2.5" targets at 375yds from a 1:8 twist. Don't for a minute believe that the "fast" rate of twist is going to affect accuracy.

You'd have to be more than a quarter inch off the lands for the bullet to clear the case before it engaged the rifling.

It is possible that you're losing velocity because the long jump to the lands gives the bullet more than enough inertia to overcome the pressure spike from being swaged into the rifling. Those bullets are really soft and since they're very light, they get up to speed really quickly. It's also possible that you just have a slow barrel. It happens. If the accuracy is good, don't worry too much about the velocity.

I'd be curious as to why the throat is so long. New rifle or just new to you?

 

[Birdhunter1]

I tried and tried and tried more with the 55 grain bullets in my .243 before finally finding a good shooting load with the 55 grain Sierra Blitzkings. I don't remember the charge but the powder was IMR 4895. On a chronograph I wasn't near the listed book speed and with another load I have with an 87 gr VMAX I found that after 175 yards the 87 vmax has overtaken the 55 grain Sierra and is traveling faster.

 

[helotaxi]

Not uncommon with the super light bullets with terrible BC's. They are terrible at longer ranges because they shed velocity so fast. Out to their practical limit they sure are spectacular when they connect with a target though!

 

[hentown]

I haven't loaded .243 in a long time, but I did load a lof of 55gr. BTs when I was an active crowshooter. I'm using a Remmy 700 VS with 26" barrel, and I've clocked some of my rounds at over 4000 fps. Don't worry about the distance from the lands; that's irrelevant for this application. Just make sure that you have enough neck tension and that you have the bullet seated deeply enough for the neck to grip it firmly. Should be at least .244"-or-so deep.