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View Full Version : Brenneke KO Slugs and Choke Info


laissezfirearm
January 16, 2001, 10:29 PM
Bought a case and did more testing this afternoon.

From a Modified choke tube, keyholing appears to begin at about the 60 yard mark.

From an Improved Cylinder, 70 yards.

From an unchoked, approximately 90 yards.

Note: By "begin", I mean that there is a noticeable gray smudge on the target left by what I'm assuming is the attached plastic wad (looks sort of like a penny and a dime standing side-by-side on their rims). Once keyholing begins, grouping degrades noticeably within 10 yards as it increases -- although I have not yet seen evidence of a full 90 degree yaw, probably due to residual weathercocking.

Note 2: Attached wad slugs appear to be much more prone to choke sensitivity than Fosters. I've regularly gotten 4-6" 100 yard groups with a scoped 870 with a Mod tube w/Fed and Win slugs from prone or off a bench.

Also, at 25 yards from a bench:

Remington 870, 20" cantilever, 1X scope, factory Modified choke tube
Federal "Tactical" Copper-Plated 00 (45 pellets total)
Pellets in 12" Circle: 34
Pellets in 6" Circle: 19

Remington 870, 20" factory Improved Cylinder w/RS
Federal "Tactical" Copper-Plated 00 (45 pellets total)
Pellets in 12" Circle: 25
Pellets in 6" Circle: 11

dZ
January 16, 2001, 11:46 PM
yo dood is that u?

where did yer web pages git too?

Yer M17 page is a valued reference

dZ

[Edited by dZ on 01-17-2001 at 11:12 AM]

Dave McC
January 17, 2001, 06:48 AM
Thanks for posting that, Laisse. I kinda wish you had used a rifled choke tube, but I think I'll do that next range day.

Does that 870 have a lengthened forcing cone?

laissezfirearm
January 17, 2001, 08:41 AM
Dave wrote:

>I kinda wish you had used a rifled choke tube

I've not noticed any advantages when combining a rifled choke tube with the pre-rifled slugs (standard Brenneke, Fosters, etc.). They work GREAT with the sabot slugs, of course -- my gun averages 3" 5-rounders at 100 yards.

The big problem with the rifled choke tubes is that they basically ruin buckshot performance, as shown below:

Four rounds Federal "Tactical" 9-Pellet 00 Reduced Recoil (36 pellets total), 25 yards:
Pellets in 12" Circle: 8 (22%)
Pellets in 6" Circle: 1 (2%!)

Those numbers = doughnut-shaped patterns. Note: A lot of folks refer to OVERALL group size, but that punishes load/choke combos which toss only one or two fliers. The 6" and 12" circles are a better method of tracking pattern density, the key to one-round effectiveness. It was used in the extensive American Rifleman article chewed over elsewhere, and using percentages makes it easier to compare apples to apples, and apples to oranges (e.g., #1 buck versus 00, etc.).

>Does that 870 have a lengthened forcing cone?

Both stock. One IC barrel with rifle sights, one #6231 cantilever with Mod choke tube. Seems I was either really lucky with the cantilever barrel (it is visibly MUCH smoother internally than the rifle-sighted barrel), or found an excellent batch of the Fed Tactical. Or both.

And yes, that barrel groups better and more consistently with the Mod tube than an IC tube. A Full tube in the same barrel, however, is moving backwards.

Dave McC
January 17, 2001, 06:26 PM
Thanks,Laisse. IMO, Modified must be hovering around the max constriction big shot will handle.Backing down to Skeet II is a possibility.

In Keith's dated but excellent tome, he mentions people seating a felt wad in the choke of their shotgun and using the size shot that lay in even layers in the choke. A bit extreme, but he knew long range shotgunning better than most anyone.

Good point about bbl finish. Run a few thousand rounds through that RS bbl,and it'll be really smooth too(G)...