[boalex207]

Okay, I know that in a round of 9 pellet 00 buckshot each pellet equates to
a .33 caliber bullet.

But what "caliber" is a 12 gauge slug ? Does .72 caliber sound right ? That is sticking in my mind for some reason.

[rantingredneck]

Yep.

Foster or Brenneke full caliber 12 ga slugs are .72 caliber.

7/8 to 1 1/8 oz usually. Most common is 1oz.

Big lead, big hole.

[RyanM]

I've cut some shells apart, and they're actually somewhere around .75 caliber or so. They apparently get squeezed down on their way out the barrel.

[Dave McCracken]

Nominal Bore diameter for 12 gauge is .729". Most slugs run close to that. I did see some older Remington Forster style slugs that went 7/8 oz and .690", but they went through most chokes undeformed.

[rantingredneck]

I recently picked up a couple of boxes of Peters slugs that were 2 3/4 7/8 oz. I wonder if they are a bit undersized. I know 50 yd accuracy was crap compared to other loads. Might be why??

[Dave McCracken]

Red, might be. However, most Forster style slugs are a bit undersized to help them get through the tight chokes of yesteryear.
My guess is try and see....

[rantingredneck]

If I have any of those left (I may have shot them all that day) I'll cut one apart and measure the slug.

I shot them side by side against Brenneke's (my favorite), Rem Sluggers, and Federal Classics and the Peters were the absolute worst. I was doing good to keep 6" groups at 50 yds from the bench with them.

[Pete409]

I've got a Foster type slug that I cut out of a brand new Remington 12 gauge shell. It measures .688" to .689" in diameter across the ribs.

[106rr]

Federal actually makes a Hydrashock slug. It is a ful diameter slug with a big hollowpoint and a little post in the middle. It is all lead unlike the Hydrashock handgun bullets.