View Full Version : Slug Rifling?? Is there a Point?

October 19, 2011, 05:14 PM
I have a 20ga NEF Break Action. It is a cylender bore choke and smooth bore.

My question is whats the point of the rifling of a slug. Does it infact have any affect on the spin of the slug.

I have been told that it is there only for looks and to reduce friction on the barrel.

I would just like to know if it does have an affect.

also I plan on making my own slugs and would like to know if anyone knows the what a good angle the rifling should be at and also the size of the hills and valleys.

Thanks for all the help,


October 19, 2011, 05:33 PM
Hi, Jeffords, welcome to the forum

A rifled slug doesn't normally spin, unless it's fired from a rifled barrel. Fired from a smoothbore? Not so much. As I recall, the rifled ribs on the slug were meant to allow the slug to swage as it went through the choke. I'm not at all sure that it's necessary, although some companies have made lots of them.

Lee and Lyman both make shotgun slug molds, available from several vendors, including MidwayUSA (http://www.midwayusa.com/Find?userSearchQuery=slug+mold). Buying a mold would be a whole lot easier than starting from scratch.

October 19, 2011, 05:41 PM
Ty i figured they did have any affect on the spin. i would like to find a way to make them spin without a rifled barrel.

Experamenting time

October 19, 2011, 05:50 PM
Ty i figured they did have any affect on the spin. i would like to find a way to make them spin without a rifled barrel.

Experamenting time

How on earth do you figure to do that? :confused:

There are all manner of slugs designed to do most anything you want. You don't have to reinvent the wheel. The Foster or Brenneke slugs works on the "bad minton birdy" principle. Weigh forward keeps it flying straight.

The Federal TruBall is twice as accurate, on average, as the standard slug. It utilizes a polymer ball at the rear to expand the slug and make it fill the bore and provide a seal.

For more accuracy, the rifled bbl. and Sabot slugs are the set up.

You're not going to gain any accuracy by trying to get a Foster slug to spin even in a rifled bbl.

October 19, 2011, 08:49 PM
KNobby, That is a VERY common misconception in slug buyers... it is easy to make this assumption... the grooves of the "rifling" are at an angle that suggests the slug will leave the muzzle with a spin.
It is not a mistake hard to make.

Once folks hang out here or other shotgun sites, it is soon learned that rotation may or may not be in play on your gun and your slug....

But to assume every new slug slinger knows the physics in play? That is the mistake of the assumer...

Not everyone is aware that these slugs are basically lobbed at a high rate of speed...

October 20, 2011, 02:15 PM
True, Hotdogs. If the "rifling" actually stabilized the projectile, it wouldn't be necessary to design them to be weight forward to make them fly straight. There may be some rotation, but to little effect.

"Rifled slug" seems to be a selling point that implies accuracy and sells slugs.

October 20, 2011, 11:23 PM
fire a rifled slug through a rifled barrel
then fire a slug through a smooth barrel
ones going to look like a drill bit went through
the other is not going to be a smooth round hole

If that test doesn't show you anything, fire each gun 5 times and compare the group

October 21, 2011, 12:03 AM
If that test doesn't show you anything, fire each gun 5 times and compare the group.

How about if Old_Painless does it?


October 21, 2011, 06:24 AM
As far as punching holes in targets... Currently I am using an old pressure bladder tank to a well water system... My slugs (20 ga) are making a ROUND hole a little over an inch in diameter... ENTRY... Exit??? Nearer to 1 1/2-3/4 but still round...


October 21, 2011, 10:49 AM
If your going to make your own slugs get the Lyman mould and use their loading data. Part no. 2654120 it is a 20 gauge sabot slug 350 grains.

October 22, 2011, 06:40 AM
well here's my experience the mossy 500 smooth bore throws shells every where. my 870 can't hold a group with sabots the shot of choice for me in buckhammer. to each their own, different strokes for different folks.

October 22, 2011, 12:14 PM
I know nada about slugs, but was wondering if choke selection could make a difference and believe there is susch an animal as a rifled choke for use with slugs.

October 22, 2011, 12:20 PM
Chokes can help or hinder accuracy in a particular gun with a particular ammo...
Mossberg suggests starting with MOD IIRC...

There are, in fact, rifled chokes for sabot type slugs... supposedly near as good as with fully rifled barrel but I have ZERO experience with any sabot type slugs... EVER...


October 22, 2011, 03:46 PM
I don't use choked barrels for slugs so i don't know anything either

Dave McC
October 22, 2011, 08:12 PM
The deer 870 here has a rifled choke tube in for the season, and a Skeet tube the rest of the time. With KO Brenekkes, groups run under 4" at 100 yards.