Wildcatting: The Short Revolution
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- Last updated: 19/12/2016
If ever there was a cartridge that turned the shooting world on its head, it has to be the 6mm PPC. It was one man’s determination Dr Louis Palmisano and his friend Ferris Pindell (hence the initials), to prove their theories correct when all the experts thought better. Well it`s all history now and the 6mm PPC remains one of the most accurate and efficient small cartridges of the world. My own involvement started with a Dave Tooley custom PPC rifle over 16 years ago now and it’s still phenomenally accurate and deadly. The small 6mm has become a bit over shadowed by the larger 6mm BR and even the newer 6mm Dasher but it still has a lot to offer the varmint and small species deer stalker.
There are a couple of versions of the PPC and it can confuse, it does me! Firstly there is the 6mm PPC USA, which is designed for a non neck-turned chambered rifle i.e. old Sakos and Varbergers. Its neck is 0.2685”, with a COL of 2.193”. Whereas the 6mm PPC as a custom round usually has a non-standard neck and COL, due to shooters preferring a tight-necked chamber for better precision and a shorter or longer throat to shoot a specific weight and style bullet. Sako 6mm PPC commercial loaded ammo or brass will not fit custom tight necked chambers!
This is why most people go the original Lapua .220 Russian case route, designed by Dr Louis Palmisano & Ferris Pindell in 1974. This is superbly made brass that has a 0.440” size rim, 0.439” sized at the base and long taper to 0.402” just at the shoulder start. The neck is 0.258” long and the overall length is 1.517” and of course the calibre is for a .224” projectile. No prob’s, case prep is simple a quick de-burr of the flash hole with a K&M de-burrer and a Sinclair primer pocket uniformer tool to ensure a properly seated primer. These two steps ensure consistent ignition.
You then expand the neck, I use a Sinclair Gen 2 expander tool with a 0.242” sized mandrel in one hit and lubed with either Imperial Sizing wax to fit a 6mm bullet snugly.
Now a trim to length of 1.4855” to fit the chamber on my rifle, using a Wilson stainless case trimmer.
I then use a K&M neck trimmer to reduce the outside neck diameter to fit my tight 0.261NK chamber. The 220 Russian brass’ neck diameter goes from 0.248” to 0.2595” O/D with 0.0095” thick neck wall thickness (9.5 thou). With a bullet loaded, the neck width is 0.260”, so only 0.0005 (half a thou) release on each side, tight but very precise. This means the cases seat exactly concentric each time and you do not over work each time they are fired. Despite 16-years use, I am still using the same 50 cases I started off with, save a few lost ones and one neck separation!
With the cartridge sorted, you need to consider the length of barrel and the rifling twist rate that would suit your needs most. There are two ways to think about it really, slow and fast or fast and slow. In other words a slow twist, typically 1 in 14” twist for light weight faster bullets up to 70- grains. Or a fast twist and slower velocities for longer heavier bullets from 70 – 95-grains.
Most people opt for the former, as the case capacity is best suited for lighter weight bullets and this is how my rifle is set up. Barrel length too is very important dependent on how you view its end use.
If it’s target shooting, then 20” is more than good enough up to 300 yards, as you are not worried about kinetic energy for quarry dispatch. However, for vermin or small deer, then that extra few inches makes a positive improvement. Being a small capacity case the PPC does best with faster powders; so Vit N133, RL10X or H322 are good choices. I use Vit N133, as it just works in my rifle with the 65-grain Fowler, Berger or Hornady V-Max, which is my all round bullet weight choice.
All data was from a 24” barrel, light weights at 1 in 14” twist and the heavies at 1 in 10”.
My Tooley 6mm PPC Custom will shoot a 70-grain bullet fine, but at 75-grains the accuracy/stability becomes iffy. So a 1 in 14” twist, as with the Tooley, is on the ragged edge of stability for anything over 70-grains!
Using bullets above 95-grains is a bit pointless in my view for the 6MM PPC, you might as well have a 6mm BR or 6MM Dasher with the correct rifling twist and barrel length to achieve better stability, accuracy and velocity potential. Also, due to the faster burn rate of the powders used, you will find that a small difference in type can make a difference in the case fill capacity. Ordinarily you will hope to achieve a 100% load density for uniform performance, but some of the faster powder like IMR 4198 or RL10X may only achieve 95% but still be accurate but a powder like Vit N133 or H322 will achieve 100% at the maximum charge weight.
I have plenty of mileage on my PPC now and it refuses to die and after an initial load development I have stuck to just one load; 26.5-grains of Vit N133, Federal GM205M Match small primer with Hornady 65-grain V-Max for 3075 fps. This is fine for small deer where legal and superb on foxes, distant crows and other vermin.
I keep it simple by using a Wilson, i.e. Arbour hand press, so I can reload in the field or on the back of a pickup if static and snipe long range bunnies or crows. The hand dies are Wilson with a 0.258” bush fitted for 2 thou neck tension and I prime with a Lee hand prime tool and dispense powder via the excellent Harrell premium culver-type powder measure. This is easy, as I set the Harrell to the 50 marker and this meters exactly 26.5-grains of Vit N 133 every time, so no need to weigh each charge. In fact, most of by reloads are written down as Harrell settings i.e. 50, 42, 91 plus two clicks, as it makes reloading in the field so much easier.
Ballistics-wise, my 65-grain V-MAX and Vit N133 combo starts at 3075 fps/1365 ft/lbs and at 300 yds it is still 2126 fps/652 ft/lbs energy. This is my small species and vermin round; it is superbly accurate, zero recoil in reality and you can spot every shot and so long as you judge the wind correctly my Nightforce scope on top (with older style ladder reticule) is calibrated up to 750 yards! Quickload ballistics program and QuickTarget are a great help as usual for determining down range performance and for printing off a trajectory chart.
Because I rely on the Tooley 6mm PPC for my go to vermin tool, a lot of the time I forget how much I rely on it for its reliability and accuracy. I haven’t changed a thing about it since I bought it, same load, scope and sound moderator, it’s just one of those rifle/ cartridge combos that works. It’s efficient and frugal on powder and light recoiling, so you can spot your shots and noise reduction with an MAE moddy is good. Barrel life is excellent; I honestly do not know how many shots I have put through her but I still use the same COL and get one-hole groups.
The only thing I would change is an ejector on the McMillan MRCT action, as I specified an extractor only, so that I could remove the fired case from the single shot tray myself, however there have been times with cold hands when I have fumbled the extraction and could not get a second round in fast enough.
The other consideration is the PPC case uses its own head size for the bolt; so if you are rebarreling a rifle, you need to modify the bolt face and then the extractor may or not work, it can be done but better to get a specific PPC head size or PPC specific action.
JMS Arms: 07771 962121, www.quickload.co.uk, Quickload and MAE moderators
Henry Krank: 0113 2569163, Lee reloading kit
Norman Clark: 01788 579651, Precision reloading supplies.
Tim Hannam: 01977 681639, Lapua brass, Vihtavuori powder
www.brownells.com: Reload kit