does the american 7mm Saami spec and the european spec make much difference for reloading a 7X65R? there is apparently a 2 mil difference in diameter?

Custom made bullets (I Think it was GS bullets) lists different specs for these.

appreciate comments.

CTGS of the World, 8th ed, pg 355,&468 lists the 7mm by 65Rmm Brenneke as a .284 dia bullet. Load data for the 7mm by 64mm Brenneke and the 7mm by 65Rmm is interchangable.

SP

Some European 7 m/ms are .286" groove diameter, some are .288" groove diameter, and some are .284 groove diameter...if you include England in Europe.

Sorry about that post above...this darned computer is on one of its jags where it sometimes posts when I hit the space key...who knows why? I don't...

Anyway, my two Holland & Holland magazine rifles in .275 H&H were both .286" grooved. My Jeffrey .280 magazine rifle (cartridge is almost identical to the .280 Ross) was .288" grooved.

The nice part is, however, that .284 bullets shot well in both. I think that is because the land diameters are about the same as US 7 m/ms...its just that the grooves are deeper.

BTW, my 7x65-R Ruger #1 has the .284" bore, but it shoots RWS H-Mantle bullets awesomely in european factory loaded ammo...under 3/4" groups at 100 yards with factory stuff. And kills Rocky Mountain elk rather well too...put two of those suckers down within 20 yards of each other in a Y2K hunt, one shot each as they ran across a trail.

[ 03-19-2003, 10:40: Message edited by: Alberta Canuck ]

Let's muddy the pond some more - I slugged my one of my .280 Ross rifles and ended up measuring the bore diameter as 0.2806" and the groove diameter as 0.2904".

GS are running off a batch of 0.2905" bullets for me.

I am now a "slug-the-barrel" convert.

cheers edi

Wow!! Big sucker!! I seem to recall that Rosses were intended to have a .288 nominal groove diameter, as did my Jeffrey. Appears they got a little lax on that one!

I presume you tried .284" bullets in it and they didn't shoot well? Wouldn't be surprised with only .002 "bite" per side. And the blow-by could really roughen the bore in a hurry, too, I'd guess.

My Ross was a .303 M1905/07 and had a very standard bore, but Rosses did face a number of manufacturing difficulties, and trials of various servitude, so I'm not too surprised at your finding.

Good argument for casting or slugging to find bore size.

Well, I first bought a Ross rifle - the action appealed to the engineer in me. Then someone gave me a case. Life was interesting - load, visit the range, fire one shot and go home to reload a second ....

Not quite true. That first one was loaded with a 0.284" 150 gn bullet - that went through the target sideways - at 20 m! I realised that maybe things weren't quite right.

Spent some time in a friend's tool room and made up a swaging die to bump the heads up to 0.288". At least that's what I was aiming for. My luck was that due to "happy polishing hour" my dies ended up producing 0.290" bullets.

I resize 8x68 cases into Ross cases - better than using the belted cases.

I'm busy fitting a scope to the rifle and hope to show it off to a Gemsbok and a couple of Springbok a little later this year.

cheers edi