Murdica’s Masterpiece — Just About as Good as It Gets
Sometimes superlatives really aren’t necessary. Just look at that target. Yes that is FIVE shots (although it truly appears like one hole). And it is centered! This remarkable group, measured at 0.039″, was shot by Lou Murdica in Phoenix on January 3, 2015. Lou drilled this group with his 6 PPC railgun. Rounds were loaded with Accurate LT-32 powder and Berger 65gr BT bullets. The target will be submitted to the NBRSA as a potential new 100-yard Benchrest record in the Unlimited (Railgun) Class. The current NBRSA record small group (Unlimited) is a 0.049 shot by Hall-of-Famer Gary Ocock in 2009.
This is a file photo with a different railgun.
This wasn’t the only tiny group shot by Lou over the weekend. Murdica shot a sizzling 0.1262 five-target 100-yard Unlimited Aggregate. That 0.1262 Agg will also be submitted for consideration as a possible record. Here are the individual group sizes: 0.104, 0.183, 0.201, 0.104, 0.039. At this match Lou won both the Unlimited and Sporter class. “It was a great weekend” Lou reported.
About the Gun
What kind of rifle can put five shots in one hole? Lou was shooting an Unlimited-class railgun. This return-to-battery rig (a Kensler railgun) allows the shooter to focus on firing at the perfect time for the conditions. Lou’s Kensler railgun (see below) features a Kelbly top-loader Grizzly action, Shilen 6-groove barrel, and March 10-60X scope. The Shilen is chambered for the 6 PPC cartridge. But there’s something special about this particular 6 PPC — read on….
Click photo for larger version:
Radical New Reamer Design from PT&G
Lou used a new chamber reamer from Pacific Tool & Gauge (PT&G) with special geometry in the leade/throat section. Called a “Bore Rider” (or sometimes “bore-runner”), this new reamer design cuts a staged, variable taper in the leade/throat area that is quite different than the taper in a typical throat. It’s a little hard to explain, so we’ve included the 6 PPC Bore Rider reamer print below. (Download the PDF file for a better view.) Experts should look at the leade angle(s), freebore, and throat dimensions. You may be surprised. Dave Kiff of PT&G says this Bore Rider design has worked successfully for other cartridge types/calibers as well. Apparently this design helps the bullet center up smoothly in the bore before the bullet engages “hard” in the rifling — or so we’ve been told.
