Help Mounting Optics!!!

JBall · Post by **JBall** » Mon Mar 25, 2013 7:40 am

Just picked up a new Marine Magnum and want to add a halfway decent optic for slugs anywhere 100-200 yards out. Was wondering if its better to go with the taped receiver and weaver rail or a Mesa tactical sidesaddle with attached Picitini?

Website · Post by **Synchronizor** » Mon Mar 25, 2013 8:16 am

I would think tapping the top of the receiver would be a more solid platform of the two options you mentioned.

For up to 200 yards though, you may want to consider a rifled barrel and sabot slugs. That range is pushing it for smoothbore slugs. You can get rifled barrels for the 870 that have cantilever rails, so you can mount the scope directly to the barrel and keep your zero when you swap it off or on.

JBall · Post by **JBall** » Tue Mar 26, 2013 9:38 am

What is a reasonable distance expectation for smooth bore slugs while still remaining accurate? I have a new Marine Magnum which I believe has the improved cylinder barrel...

JBall · Post by **JBall** » Tue Mar 26, 2013 9:38 am

18.5" sorry LoL

Website · Post by **Synchronizor** » Tue Mar 26, 2013 1:27 pm

JBall wrote:What is a reasonable distance expectation for smooth bore slugs while still remaining accurate?

It'll depend on the slugs and the shooter. With a vent-rib and an IC choke tube, I can put Remington Sluggers (slightly-oversized Foster-style slugs) into a human silhouette at 50 yards if I don't botch my trigger pull (I've been meaning to get a lighter sear spring for that kind of shooting). With good technique and properly-compensated sights, they could probably reach out farther, but between 50-100 yards, most smoothbore slugs slow down and start dropping a lot due to their poor aerodynamics. I've heard other slug types like Brennekes or Plumbatas are a little better than Fosters at long ranges, but not by too much, because while they may be a little more aerodynamic or stable, they still suffer from the same crappy sectional density.

Sabot slugs are much better than smoothbore slugs for long-range shooting because they're built like rifle bullets and spin-stabilized in the same way so they're more aerodynamic and precise. In 12ga, sabot slugs are usually around .50-caliber, far better than the .73-caliber 12ga bore diameter for retaining velocity. For slug hunting past 100 yards, this would probably be a better way to go. If you're thinking of making shots at those ranges for combat purposes, I'd start looking into rifles.

JBall wrote:I have a new Marine Magnum which I believe has the improved cylinder barrel...

JBall wrote:18.5" sorry LoL

Does your Marine Magnum barrel have an IC choke? Remington's website and parts list describe all nickel-plated barrels as 18" cylinder bore barrels, but by your pictures, that barrel does look like an 18.5", so maybe Remington changed it.

Kentactic · Post by **Kentactic** » Tue Mar 26, 2013 5:46 pm

150 is on the outer limits of a rifled slugs reliable accuracy. I say this as i can put 3 slugs in a 3" group at 50 yards. That spreads out to maybe 10" at 100 yards and its kind of all over the place at 150 yards. All shots being off hand standing with just a front post sight. In my experience the slower slugs are more accurate. Thr diameter of rifled slugs can vary greatly. A slug with a diameter closer to bore size would probably tend to be more accurate.

Kentactic · Post by **Kentactic** » Tue Mar 26, 2013 6:30 pm

Sorry i got carried away. For sure the most reliable way to mount an optic would be directly to a tapped reciever with a rail.

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