.303 brit..groove / bore question

[atr]

Just slugged a .303 British Mk4 #1.....lend lease rifle made here in the US
this is a two groove version
the bore measured at 0.308
and the groove at 0.316
which means that the grooves themselves are 0.004 deep each...

Just wondering,,does this match what other have found in similiar rifles???
thanks
atr

[docone31]

I heard tell of larger bores!! With mine, when I use jacketed, I use .312 rather than .311.
Yours will be a good candidate for patching! They do well wrapped up.

[VintageRifle]

My Savage No4 MkI* has a bore of .304 with grooves of .3155.

[JeffinNZ]

I'd remeasure. That bore does not sound right. I think you will find it .303-.304.... hopefully.

[atr]

OK,,,, I re-measured and Jeff was right to suggest it..
the bore measured 0.3045 - 0.305

[JeffinNZ]

Par for the course with a two groover. My .303 Pygmy measures .317 in the grooves.

Can I recommend the CBE 316 240 bullet from Jim in AU? Casts at .3165 in WW. Shoots like a house on fire.

[curator]

Enfield 2-groove barrels sometimes shoot cast very well, sometimes not. There's a good article on Steve Regwell's website about another shooter's experience:http://www.303british.com/id37.html

[dualsport]

WOW!! Read that article, it's a gold mine for .303 shooters.

[Pirate69]

I recently picked-up a Savage N0. 4 Mark 1. It mics 0.315" as well and is a 2-groove barrel. Still working on getting the copper out of the barrel with Sweets. Have not shot it yet.

[218bee]

My Savage is same as yours...have not played with it yet but was told since bore was so small compared to the two "large" grooves that boolits may not need to be as large as ya might think as the metal has to be displaced somewhere right?? Kind of makes sense I guess...but as I said I have yet to shoot mine. Please let me know your findings and I'll do the same

[Pirate69]

Will do.

[wellfedirishman]

That's a good article linked above.

I have a nice No 4 Mk I Long Branch sporter (I believe it is a commercially re-made sporter, post WWII, by Parker Hale). The 2-groove bore is pristine. It shoots great with military surplus ammo and jacketed reloads, but won't shoot cast worth a damn.

I have tried .316 booits (unchecked), .314 gas check boolits, and .312 gas checked boolits. All lubed well with Alox, over about 16 grains of 2400 or 14.5 grains of Green Dot.

All keyhole like nobody's business. In fact the keyholing is so good, I get a nice GROUP of keyholes at 50 yards. A perfect set of keyholes in a 6 inch circle.

I am going to try using a Cream of Wheat (COW) filler next. Per that article it might help.

I have not slugged the bore (since the bore looks brand new, I don't think it is worn). Also, I don't have any mold that drops bigger than 316 anyway.

Any thoughts?

Edit to Add: The 314 gas check boolits I mention above shoot great in a beat-up worn out old Mosin Nagant I have, over 14.5 grains of Green Dot. So I don't think the boolit is the problem.

[docone31]

Paper patch.

[Piedmont]

wellfedirishman, Slug that thing, so we can all quit guessing. I have a Savage that is .304/.316 and it shoots well with a .316", .305" bore ride Old West 220 grain mould. Initial testing with an all body bullet of .318" that probably fit the throat better were lackluster to say the least. I think there really is something to these two groove rifles liking a long bore ride nose that fits, and probably something to not going as much oversize on these as we usually do because of the finning tied to those huge lands (i.e. huge with respect to the bullet metal they displace).

[Multigunner]

I haven't tried cast in my two groove Savage yet, but its a sub moa rifle with taylored handloads. Bore slugged at .304 and .314, which is about as tight as these get. It might have been .303 when new, I had to polish out a lot of chatter marks midway of the bore, either from worn factory rifling machinery or more likely a third world user banging a steel cleaning rod around in it.

From what I hear the British Two Groove has wider grooves than the Savage and shoots cast much better.

I hadn't intended to try cast in the two groove but I'm gathering up what I need to try cast in my No.1 MkIII so I'll give the Savage a try with the same loads and make a comparasion.

[Pirate69]

wellfedirishman,
I have to laugh at your grouping of keyholers. Your luck sounds about as good as mine on certain things!!!:smile: