Questions about bore riders

[Clinton]

I bought the Lee C309-170-F to load 308Win not knowing it was a bore rider. I've had some problems (and lots of confusion) getting it to shoot accurately. Several people recommended I get the C312-185-1R and so I did and after casting them realized...... it's another bore rider. So I began thinking "Is it even possible to design a heavy 30 cal lead bullet that isn't a bore rider?" I'm guessing the reason these bullets are bore riders is because they have to be designed that way to get that much lead into the chamber without the base of the bullet extending down past the neck into the powder. Am I correct in this?

I've also done some reading on these forums and it seem generally accepted that rifling engraving on the bullet is more preferable than no engraving. Will this work in a semi auto? Would you not need a decent crimp even in a bolt action with this kind of contact?

[upnorthwis]

You will definitely need a crimp for a semi-auto. Or the boolit will get pushed farther into the neck. I do not crimp for bolt actions. But maybe it's because my boolit just fits in there with only slight engraving.

[Clinton]

That was the problem I originally had with my first attempt at loading bore riders. The bullet got pushed back into the case with my bolt gun.

[detox]

That was the problem I originally had with my first attempt at loading bore riders. The bullet got pushed back into the case with my bolt gun.

You need to crimp to prevent bullet from being pushed back when chambering. When ejecting a loaded round be sure to hold muzzle up to prevent gun powder from spilling into action. Your problem is common with tight fitting bore rider.

Be sure to size bands .0001-.0005 smaller than free bore for best accuracy.

[Clinton]

Still nobody has addressed my other question. Are all 30 cal cast bullets above 170ish gr bore riders?

[Larry Gibson]

Still nobody has addressed my other question. Are all 30 cal cast bullets above 170ish gr bore riders?

Basically. A .30 caliber cast bullet that fits between the base of a 30-06 or 30-30 length neck and the leade and then has a the ogive starting there will weight 165 gr or less. The NOE 30 XCB bullet is so designed. A heavier bullet similar to a scaled down 323471 could be designed for long necked '06 and 30-30 chambers if they were throated with a longer free bore such as the 300 Weatherby. The 300 Weatherby gives up some with it's short neck.

Also; "I'm guessing the reason these bullets are bore riders is because they have to be designed that way to get that much lead into the chamber without the base of the bullet extending down past the neck into the powder. Am I correct in this?"

That is essentially correct.

Larry Gibson

[Clinton]

Ok thanks. That takes some of the mystery out of all this for me.

[Le Loup Solitaire]

Bore-rider bullets were described by Col. E.H. Harrison in the NRA reloading book in an article investigating the performance of cast bullets in 30 cal rifles. He determined that they worked well in rifles having 2 groove rifling such as the O3-A3 and 5 groove rifles such as the 1917. The rationale was that in barrels where the bore circumference was mostly lands, then the bore riding section of the bullet would be much more positively guided by the lands. A long nosed bullet such as the Lyman 311334 (or similar bullets from Lyman"s series of 31133- designs or the old Saeco RG-4...now the 301 were all good choices. Some of Lee's current designs appear to qualify as well. An important feature has to do with dimensions. A bullet body (with the bands) has to measure at least .310 and the nose or bore-riding section must be at least .301. Bullets casting less, particularly the nose section are prone to tipping/tilting off axis in the bore and exiting the barrel in that mode=wild shooting. The NRA loading book/Col Harrison's work may be found and read in the Cast-Pics section. LLS