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Dave McC
January 31, 2001, 12:45 PM
Took a little furlough from Daddying this morning, and hit the range.

I tried the KO Brennekes this year for deer, the one doe I shot went less than 75 yards and went down within sight. Internal damage was of the order expected from any 12 ga slug, and accuracy was excellent for me and these tired old eyes. I zeroed and group tested at 50 yards, a long shot where I hunt in the brush and swamps of Md's Eastern Shore.

Then, one poster here mentioned he had tried these at 100 yards and saw some keyholing. This indicates destabilizing, and might be indicative of longer range inaccuracy.

My 30-30 needed rezeroing, and I grabbed an 870 also. This was my HD 870, which was already dialed in for them at 50 yards, and was a chokeless 18"bbl, with peep and some mods.

My thought was that a smoothbore would show destabilizing better than my Deer 870, which has a rifled choke tube.

So, I shot the 94 until I had it printing 2" over POA at 50 yards, moved the frame back to 100 yards, and eased into the best shooting position I could with the 870.

Loading singly, I slow shot three rounds. This was from a rock solid bench rest, with good form and trigger control.

Then I walked down and got the target, and it was good news, bad news time.

Good news, the group was centered and 6-10 inches below POA. This load was 2" high at 50, so drop was probably about 9-10 " at 100. Group size was a measured 5", outside edge to outside edge, call it 4.25 CTC. Certainly acceptable by my standards.

Bad news, all three rounds showed signs of keyholing, entering the target at a slight angle. All three angles were different, of course.

And while a single 3 shot group is by no means an exhaustive study, some conclusions can be drawn.

1.while accuracy was acceptable at 100 yards, the possibility of further degradation means this is a 100 yard load for deer or whatever.This is no major drawback for my purposes, a long shot where I hunt is 50 yards. Everage distance of the deer I checked in was about 30 yards.

2.This was a worst case slug gun, with a barely legal bbl and a smooth bore. A rifled choke tube or a fully rifled bbl with a twist suitable for the load and a longer bbl to build up more velocity would add some distance to accurate shots.

3. Your results may differ. I highly recommend everyone trying out loads until they get what works for them. I like the KOs because, for the first time in a decade of having two slug guns, both "Like" the same slug. And the price is nice also.

Nest time I hit the range, possibly as soon as tomorrow, I'll take the Deer 870 and screw in the rifled tube, just to compare and report further on this...

Thanks.....

KilgorII
January 31, 2001, 09:49 PM
Interesting as always.

Let us know how the rifled choke tube affects it. I've got a rifled tube I've never used because the barrel with the screw in chokes it the 28" vent rib. The rifle sighted 20" (or 21" can't remember) is fixed IC. I think I'll carry it to the Tulsa gun show in April and see about swapping for one with the tubes.

You think the rifled tube is enough rifling to use sabots?

Perhaps you could carry a IC or skeet choke with you and try that so that you have a true comparison using the same gun/barrel combo with only the chokes as variables.

Anyway let us know what you find out.

KilgorII

Dave McC
February 1, 2001, 12:52 PM
Kilgor, that's what I did, and the results have me scratching my head....

Hit the range again this AM, and brought both the 30-30 and the Deer 870 with its rifled and IC tubes. Shot one group at 100 yards with the 30-30 to see if I was shooting OK(3 shots, under three inches) and snuggled in behind the 870 wearing the rifled tube, as it was for the deer season.

First shot was a called flyer, and hit high. This shotgun was zeroed like the other one, 2" high at 50 yards. The next three shots, slow fire, hit a little above POA centered for windage,not low like yesterday, and into a group 4 1/2" ETE.

Then, I screwed in the IC tube, and went for a three shot group. This time, I didn't glass after each shot, but fired them off slowfire. I then looked through the binocs and, shazam, NO NEW HOLES!! Couldn't tell if they were in the same zipcode....

I don't usually miss clean off the frame, and this has me wondering what is going on, as well as why two different shotguns, set up and zeroed identically at 50 yards, have vastly different POIs at 100.

Oh yes, inspection reveals that the KOs were still keyholing, tho the smeared part was smaller, indicating it was a little closer to stability. Go figure...

laissezfirearm
February 2, 2001, 07:15 PM
>Then, one poster here mentioned he had tried these
>at 100 yards and saw some keyholing. This indicates
>destabilizing, and might be indicative of longer
>range inaccuracy.

That'd probably be me, and as I have reported
before, the keyholing of attached-wad slugs like
the Brenneke KOs is dependent upon the degree of
barrel constriction.

Foster-type slugs *can* produce great groups (in my
Rem 6231, roughly 5" at 100 yards) out of a Modified
choke tube.

The accuracy of the attached-wad slugs I've tried
is apparently MUCH more choke-dependent.

With the Brenneke KOs, my Mod can get acceptable
groups to maybe 65 or 70 yards. My IC knocks it
out to perhaps 80 yards. Cylinder bore, maybe
90. Other similar loads may perform differently.

Of course, every barrel is different.

Dave McC
February 3, 2001, 10:54 AM
Couldn't remember, Laissez, who it was. Old age, you know(G). Sorry.

And it sounds like you're doing proper research.

A couple of comments on benchtesting your slug gun.

One, I shoot off my hands,no sandbags, doing this type of testing. I want to know how it shoots when I hold it, not from the bags. It's not so obvious for shotguns, but an occasional rifle can have two widely diverging POIs when done both ways. My forward hand is supported from a padded rest, my other elbow grounded and the whole thing pretty solid.

Two,you'll never hear me claim that benching is pure, unadulterated fun.Inadequate padding and/or bad form can turn a session into an minor ordeal.

I take an anti-inflammatory first,take my time and don't worry about things.

laissezfirearm
February 6, 2001, 05:17 PM
> A couple of comments on benchtesting your slug gun . . .

SOP is four rounds (the number in my shorty sidesaddle) from prone, single-loaded, at the distance specified.

If I use a bench, I'll mention it -- generally when I'm shooting EXPENSIVE stuff, or don't have enough on hand for more than one or two tries.

Don't set my sights to accord with bench results, just measure the groups. Learned that much from shooting High-Power Rifle.