6.5-06 load data

[Freezer]

I started reloading for my 6.5-06 and I'm using Nosler load data. They have a max load of 46.5 gr of IMR 4350 under a 140 gr bullet. My 280 Rem has a max of 53.5 and the 270 ha a max of 50.8. Why is the 6.5-06 so light? I should get 2869 fps with a 79% load. I'm just curious!

[CPJ 2.0]

Smaller bore size equals more pressure. That’d be my guess.

[GrapeApe]

Smaller bore size equals more pressure. That’d be my guess.

Yep.

There is actually a term for it, "expansion volume"
Moving a 0.308" bullet 1" down its bore opens up a much larger volume than moving a 0.224" that same 1" down down its smaller bore

A general rule of thumb, using cases of similar capacity. The smaller the bore, the slower the optimum powder, the bigger, the faster.

[jaywapiti]

My 2003 Sierra book 65-06 w/Sierra 140 gr.SBT all loads are max
IMR 4350 51.5gr.
AA 4350 50.5gr
H 4350 50.0gr.
Federal re-formed 25-06 cases, Fed 210M primers, trim to length 2.485
26" bbl 1/8 twist

JAY

[Freezer]

My 2003 Sierra book 65-06 w/Sierra 140 gr.SBT all loads are max
IMR 4350 51.5gr.
AA 4350 50.5gr
H 4350 50.0gr.
Federal re-formed 25-06 cases, Fed 210M primers, trim to length 2.485
26" bbl 1/8 twist

JAY

Thank you! I couldn't find much online for the 6.5 and 46.5 of IMR 4350 @ 2863 seemed a little slow considering. What velocity will 51.5 grains of IMR 4350 generate and what is their starting load.

For now I have 40 rounds loaded. This is a LOOONG time project that is finally done and I'm starting to tinker with loads. This is supposed to be my distance rifle but with the current load it only matches my 280 Rem. I need to study some ballistic charts and find better reload data.

[jaywapiti]

Starting loads to max , 46.9 @ 2700fps, 48.7 @2800, 50.6 @2900, & 51.5 @ 2950fps

Just for reference P.O.Ackley lists 53gr. 4350 for 3175fps no bbl. length given.

JAY

[Elk Creek]

Another look from Hornady.

[mitdr774]

Based on multiple range trips with my R700 6.5-06 with a 26" barrel, the Nosler load data is optimistic on velocity. I am using Sig .270 brass converted to 6.5-06. I have used the 140-142 load data for both 142 and 150gr ABLR bullets. I find the 150gr is only slightly slower than the 142gr at the same charge weight. The best group size loads I have shot with the 150gr and IMR 4350 was 45.0-45.1gr. This should have resulted in a velocity of around 2790 fps. Actual velocity is more like 2650 fps. I found my max load with the 150gr ABLR and IMR 4350 to be around 3gr over max and it resulted in an average velocity over about 20 rounds of 2895 fps with a fairly low ES for hunting ammunition loaded on non fancy equipment. This same powder charge results in the 142gr ABLR running about 30 fps faster.

I am probably going to run the 142gr ABLR over a charge of RL-26 that averages 3050 fps for my upcoming pronghorn trip.

I have found that with my rifle and brass, just about every book load I have tried from Nosler or Hornady has been optimistic compared to recorded velocity. Some more so than others. I have been using QuickLoad and it has been more accurate with velocity predictions, but it has been off a bit on some of the pressure predictions.