Reply with quote #9
Per my experiments, a 1 in 14" twist 243 barrel will stabilize a .935" long 75 gr Vmax bullet at 3000 fps out to 50 yards, but not to 100 yards.
What does it all mean?
The bullet must be shorter than .935", like a
.243, 85, Sierra SP 1520...... 0.910" long
.243, 70, Hornady SP 2410....0.793" long
.243, 80, Speer SP 1211.......0.880" long
Reply with quote #10
My 6mmBR with a 1-14" twist shoots like a laser with 65 grn. Hornady V-Maxes with a stiff dose of 34.5 grn. Varget, CCI sm. rifle mag. primers 450. The same bullet does well with 31.0 grn. VV135 with Fed. match primers. For 68 grrainers, I drop the charge a little and they shoot almost as well as the 65's.
Bear in mind these loads are safe in my rifle but there is no guarantee that they will be safe in yours. Reduce load for safety and work gradually up.
Reply with quote #11
Thanks for the info guys...atleast it gives me a good place to start...and yes i will work up to your loads
Reply with quote #12
I read this and other similar posts and decided to make a spread sheet containing the dimensional data for the bullets that I have on hand. Attached is what I came up with.
The OAL was measured with a regular vernier caliper. The Ogive OAL was measured with a Stoney Point tool in the vernier caliper. The boat tails were also measured with the vernier, but there is some approximation in doing so. Even with this, the data will provide a good basis for comparison. Incidently, while measuring at least 6 each of the bullets listed I was impressed by the consistency of the Hornady and Sierra bullets. The Bergers varied in OAL quite a lot. Another interesting observation is that is that all Hornady V-Max bullets and the Sierra 60gr HPFB bullets shoot very well in my .244 Rem and my 6mmBR with a Hart 1:14" 21" barrel. The same has been found true in my buddies .243 Win. Looking at the dimensions, the 65 gr V-Max and 60 gr Sierra HPFB have a bearing surface length of .348 and .375, interesting. Many say to get the 75gr bullets to shoot well you have to push them to about 3300 fps. I have not tested this.
If anyone has additional data, I will ad it to the spread sheet and edit it here. Thanks, Peter.
There are 2 pages of info here. In Excel click on "sheet 1" and then "sheet 2".
243_Bullet_Specifications.xls (20.50 KB, 67 views)
Reply with quote #13
My 20 inch 6br XP loves the 66 grain Fowler flat base, H-322-7 1/2 Remington's
out of a 1 in 14 twist Hart barrel....
It's a nasty little groundhog gitter.....
Reply with quote #14
Preacher, What did you think of the spread sheet data? I just ordered a sampler pack of 66's from Fowler on Friday. Hopefully they will work as well in my rifle as in yours. Thanks, Peter.
Reply with quote #15
if you ever get your hands on those 66 grain Fowlers, please let every one know, and then run right out and get a lottery ticket ASAP.
Maybe the kid finally woke up to the fact, that his Father made a heck of a 66 & 80 grain bullet, and if he gets it in gear he can possibly do the same...
I'm still waiting for conformation of my last order placed a year ago come June....
I couldn't get the bullet link to open on my new G-5
Reply with quote #16
Preacher, I ordered some Bart's 66 gr wedge bullets the other day. I have not yet received them. I can try to PM you the Excel document. If it does not work email me and I will send it direct. I have another sheet where I calculated how much of each of the bullets will be in the neck on my rifle. Even though it is specific to my rifle, you can see a trend for comparison. Take care, Peter.