Groove diameter bullets

[2Tite]

I've got a mold that casts at .408 in my alloy. My groove diameter is .408. I've never tried groove diameter bullets I've always used bullets that were .001 or
.002 over groove diameter. I'm sure some of you must have experience with this.
Does it work well? I realize that trying them is the answer but I don't want to waste much time at it if some experienced folks have had bad luck with it.

[Piedmont]

A gas check will help and it will help to have a tight chamber. I have a tight chamber .40-65 that I have done this with and it worked. Most of my shooting was with smokeless. It will work even better with blackpowder.

Can you give us any more specifics?

If your chamber can handle a larger bullet remember that you can always Beagle that mould and get more diameter.

[geargnasher]

Depends, depends, depends. Only way to know is try them and see. They'll shoot, the question is do they shoot straight, and do they lead the bore.

Gear

[runfiverun]

i shoot 358 in my 358 win at something like 2400 fps.
and 2245 in my 223/220/and 22-250
and 323 in my 8mm mauser.

yeah all squeekers. they are also three of my most accurate rifles with cast boolits.
hugely oversize is NOT necessary,and in fact i believe it's contrary to accuracy.
i could go on.

[ku4hx]

When I started out circa 1970, I followed Lyman's advice pretty much exactly. If they used industry standard groove diameter in their loading so did I. For the most part it worked out well with good accuracy and some leading. But, I was young and dumb and had lots of energy and scrubbing a Blackhawk bore was simple. Especially when a shooting session usually consisted of 50 or fewer rounds. I was loading .38 Special and .357 Magnum and getting every last load I could possible get out of a case before discarding it. Then I started growing up in the hobby and realized there was more than one way to skin a cat.

If groove diameter meets your needs and does what you want, go with it. If not, you'll need to experiment with other diameters and maybe even alloy composition. The process of building a load is hardly a waste of time in my opinion, it's more a labor of love for me. It's likely to mean multiple trips to the range for sure, but isn't that what it's all about?

[williamwaco]

Depends, depends, depends. Only way to know is try them and see. They'll shoot, the question is do they shoot straight, and do they lead the bore.

Gear

Don't ever assume it won't work just because "they" say it won't work. Try it for yourself. You will often be surprised and occasionally pleasantly surprised by the result.

The worst thing that can happen is that they lead or spread, or both. That would mean you would be "forced" to make another trip to the range. OMG what a horrible fate.

.



.

[paul h]

The only way to find out is to shoot them in your gun.

Personally I only pull out the caliper and micrometer when I'm having problems and need to trouble shoot them. I'll choose a lube sizer that is 0.001" over bore dia, but more often than not I can't tell you what my bullets as cast dia is as to me the most important dimension is the group size, not the bullet size.