The term is used enough, and I have a good idea of what it means, however a question comes to mind. I am thinking of building a 6.5 WSM, with a 30" 3 groove barrel. It is a barrel burner, I would guess its over bore as well (depending on definition).

My question: can that cartridge be loaded to a reduced load say in the .308 range, and then stepped up when long range shooting requires a hotter load. Will the reduced loads save the barrel and throat?

Thanks for the replies in advance, and as they say no question is stupid.

Frank D

The short answer is,YES. Any time you reduce the amount of powder you lessen the available fuel that does the damage. Keeping down the number of rounds fired in a row will also help. High-Power Rifle competitors, and varmint hunters will wear out a bbl faster than a deer hunter will. There bbls will not last as many rounds because they shoot several rounds in a short amount of time, heating up the bbl causing increased wear. Let your bbl cool while testing ammo. I usually shoot only 3 round groups whin testing Magnum rifles, only shooting 5 round groups after I have found a good load. After a couple of 5 round group tests I go back to 3 rounds for checking zero and other range work.
Norma is a firm believer that Moly coated bullets prolonged bbl life in their 6.5x55, others are not so sure. I shoot Moly bullets in my competition rifles, but I still clean them after each days shooting, I have had no problems.

Frank,

I have never loaded for 6.5WSM but have loaded for most things and with reduced loads.

Yes, you could easily makes loads that will approximate 6.5/08.

Here is general guide but it is not specific to the 6.5WSM

Basically there are two approaches. Firstly you can simply use what might be considered as starting loads for the powders which are appropriate for full power loads in the calibre. That will bring calibres that use the H&H belted case size back down to equal top loads in the 30/06 size calibres

Secondly is to use powders like Varget. A maximum load of Varget will be about 80% of the powder amount used for H4831 or Reloader 22. Let's assume that a maximum load in calibre xyz is 70 grains of H4831 or Re22. Varget will be about 55 grains and as such you would work around the 50 grain mark.

To get the best results the ideal is to be able to reload at the range.

What normally happens if using powders like Varget, 4064, 4895 is that you will finish up with powder weights that are around the weight of powder used in a smaller case on the same calibre but velocity will be less.

Quite often the accuracy produced by such loads is extremely good and sometimes they will in fact be the best in the gun. With a good barrel point of impact is a bit below normal full loads. Usually with calibres that have a large capacity for the bore the point of impact is much closer to full loads than is the case with calibres like 375, 460 Wby, 458 etc, that is, those with small case capacity for the bore.

By using lighter bullets in calibres such as the 6.5 WSM, 270, 7mm Rem etc, quite often reduced loads with powders like Varget when used with light bullets will shoot to about the same point as normal full powered loads with heavy bullets.

Accuracy is generally influenced a lot more by seating depth and powder charge with such loads than is the case with normal loads. With charges that are too light often the groups are quite large but the shots are fairly evenly spaced. As you increase the load the groups come down and when you go to far they will start to open again. In general peak accuracy is achieved at lower pressures than is the case with using the normal powders for the calibre.

Hope this helps.

Mike

THANKS FOR THE INFO, I AM VERY CLOSE TO GETTING THIS PROJECT INTO THE BUILDING PHASE. I LIKE THE IDEA THAT THE RIFLE CAN BE USED WITH A REDUCED LOAD, AND THEN STEPPED UP TO REACH OUT WITH IT.

FRANK D

Frank, take a look at www.longrangehunting.com. there's a guy on there named S1 who is very versed in 1000+ yd. shooting that has one of those wildcats. He LOVES it. I think he's using a 3 groove barrel also.

If you neck down a 20mm cannon shell to a phonograph needle your over bore capacity!!

Many of our magnums are overbore capacity today but that doesn't make much difference..Like a sports or racing car not getting good milage, but they are fast...

Frank,
Got a 6.5 WSM and love it. Mine is for hunting (25" bbl). I download it sometimes for fun, and when I'm not trying to reach the next county. I've tried the data for the 6.5 Rem Mag using powders faster than 4350 (detonation possible with the slower powders?).