Slugs vs. the backbore

9mmMike

New member
OK team,
Riddle me this.
I have a barrel for my 870 that was marked as IMP CYL. Measurements showed the real deal to be .737 bore with .014 poc. Closer to Skeet-2 IMO but we'll let that one go.
I had the barrel back-bored as part of a roll-your-own experiment so now we're looking at .022 poc.
The question is this:
Since the choked end of the barrel is still exactly the same size as when it left the factory, have I affected the ability to safely shoot slugs? Most of the posts I've seen say it is fine to shoot slugs from IC barrels. The opinions begin to vary the more choke that is added. This barrel is no longer IC but the small end is the same as original.
Does this make sense?
All opinions are welcome.
Thanks,
Mike
 
I think you are safe. but could be interesting finding out how it groups with different slug loads. You'll never know either till you try it in your gun.

Sam
 
I will be taking this SG to a class this weekend. We'll see how she works. I think I'll bring a spare barrel as well.
Mike
 
Well we're back. The couple slugs that I fired at 9" paper plates were only about two inches apart, probably less. These were shot at 25 yds., no bench, standing. I am not the world's best longgun shooter so it might have been better with someone else at the controls.
The second day of shooting (the intensive day) was cancelled due to rain and scary lightning.
We worked on drills inside instead.
So, the answer is...
It shoots fine with the factory IC choke and the backbore did not hurt accuracy a bit. In fact, my slug group was the best of the bunch which included another 870, a Benellii M1 & a 70's vintage 1100.
I will test some more when I can and update this thread.
Mike

edited to correct plate size.
 
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You have not affected the ability to safely shoot slugs. The rifling on slugs is a crush zone for tighter chokes. A friend of mine shot alot of slugs out an old mosberg that was a modified choke. No problems just a little less accurate. It shouldn't be a problem till you get to full choke range.

I use IC in my 1300 with excellent results.

Shok
 
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