Showing posts with label Custom Rifle. Show all posts
Showing posts with label Custom Rifle. Show all posts

Sunday, 12 October 2014

20 PPC, Custom rifle from second hand base rifle

We all know how popular the PPC cartridge has been to Benchrest shooters although newer designs are now shining through. It is partly due to the fact that Dr Palmisano and Ferris Pindell designed a superb efficient cartridge shape from the off (Palmisano Pindell Cartridge, PPC). Some cartridge designs just work much like a well tuned race engine.


Introduction

We all know how popular the PPC cartridge has been to Benchrest shooters although newer designs are now shining through. It is partly due to the fact that Dr Palmisano and Ferris Pindell designed a superb efficient cartridge shape from the off (Palmisano Pindell Cartridge, PPC). Some cartridge designs just work much like a well tuned race engine. It’s a blend of internal and external design, where the harmonics and thermal dynamics of the powder burning cycle just synergise to their maximum thus producing super efficient, clean and un-turbulent and consistent propulsion for your chosen bullets.

It’s no chance that the original 6mm PPC case has been expanded, necked down and modified since its design. I run a nice Venom .17 PPC and at the other end of the Spectrum is the improved 6mm Dasher, I have even seen 30 cal versions.

But like the original 6mm design the .20 PPC is a real honey and specifically designed for the varmint hunting market but also doubles as a great benchrester as well.


Cartridge design

I have said this before but think about those tiny .20 cal bullets as they fill a very efficient void between the .17 and .22 centrefire, in fact 0.172 and 0.224 calibres is some 0.052 thousandths of an inch which in ballistic terms is huge. That’s like having a 0.243 calibre and 0.308 calibre with no 0.257, 0.264, 0.277 and 0.284 calibres between them, and where would we be without the 25-06, 6.5x55mm, .270 Win or any of the 7mm calibres? 

The 20 PPC and 20 PPC Pup are a classic varmint round. The PPC is based on a modified .220 Russian case and is transformed when necked down to 20 calibre, the case is super efficient and uses less powder than larger .20 calibre rifles to achieve the same velocity. This means less fouling and barrel erosion. The .20 PPC with 24 inch plus barrels launches a 39 grain Blitz King at 4000 fps whilst using 28 grains of VIT N 133 powder, a 1 in 11 rifling twist is best although a 1 in 9 would be superb for the larger 50 grain Berger bullets for extreme range Varminting. A 32 grain V-Max can be pushed to 4300 fps with only 27.5 grains of H 4198 powder. The .20 PPC Pup is just a shortened 20 PPC case for use in Benchrest matches but also makes a great vermin/fox load.


Bullet Choice

At first only Hornady offered a 33 grain V-Max projectile and Berger a 36 grain hollow point. This was enough to wet the appetite of small calibre shooters worldwide, me included and from this we have four main manufacturer`s producing bullets as well as several small, independent bullet makers.Hornady offer a 32 and 40 grain V-Max bullet designed to expand rapidly on the target yet deliver superb accuracy at long distances. The 32 grain bullet has a BC of 0.210 whilst the 40 grain V-Max has a BC of 0.275 making them great varmint bullets. There is also a 45 grain Soft Point design and is good for foxes and has a BC of 0.245.

There are also a non toxic NTX weighing in a 24 grains and a new Z-Max 32grain varmint bullet that I have not seen yet.

This is also true of the Sierra Blitz King range, again a 32 grain bullet, BC 0.221 was chosen as the lowest weight bullet and at the top end a 39 grain Blitz King, BC 0.287 offers great accuracy long range potential and terminal ballistics.

Berger synonymous with Match grade bullets had a great range of .204 bullets but have reduced them sadly. Still the lightest is now the 35 grain Match Grade FB Varmint with BC of 0.176 then the 40 gr Match Grade BT Varmint BC 0.225 and finally highest BC 0.381 for the 55 gr Match Grade Long Range BT Varmint but requires a fast twist rifling for stability.

Nosler joined the Twenty calibre race late but now produces two .204 calibre bullets from their Ballistic Tip range. The 32gr and 40gr Ballistics have good BC`s at 0.206 and 0.239 respectively.


Rifle build

It`s nice to have a custom rifle build but let`s face it, they can be very costly so there is no reason a suitable donor rifle cannot be sourced for the purpose. Only problem with the PPC case is that the head size is 0.441 in between the .223 of 0.378 and .308 of 0.473 inch.

Therefore a PPC bolt or some modification needs to be done by your gunsmith, not a big problem but needs to be done and also if the rifle is to be a repeater then feeding a boxy shaped PPC can also be problematic.

As luck would have it a Sako 75 in 22 PPC turned up and was the perfect donor rifle. The barrel was shot out so a new barrel was all that was needed to get the project under way.

A Shilen Select Match grade barrel was chosen and supplied in a number 17 profile which translates to Rem Varmint profile. Rifling choice is key to stabilising those .20 cal bullets. 1 In 11 or 12 are good for the lighter bullets of 30-45 grains but if you want to use the heavier 50 or 55 grain bullets it needs a 1 in 9 twist rate.

We opted for a 1 in 12 twist as the 39 grain Sierra Blitz Kings were our choice and we wanted to push them as fast as possible without over pressure or stress to the bullet. A half inch UNF thread was also cut to the muzzle.

Chambering options are plenty for the 20 PPC dependent on the bullet and thus throating needed. You can go neck turned dimensions or non neck turned if you like and I like a tight throat myself oh ah and so went for a 228 neck dimension on the reamer so a loaded round would have 226-227 thou loaded diameter with bullet for a 1.0 or 0.5 thou per side clearance on firing, tight but very concentric which is why you go the neck turning route in the first place.

A set of Wilson 20 PPC or 22 PPC neck dies can be used and a bush of 0.225 inch was used for a 2 thou neck tension.

The seater die was a 22PPC with a 20 cal stem fitted and manual set for bullet depth although a calibrated replacement head can be ordered if necessary.

Cases are virgin Lapua .220 Russian brass necked down to .204 cal with a series of nitride bushes and there is then a neck turn with a K and M turner for a close chamber to neck fit.

As the Sako 75 was a heavy barrel varmint version anyway the barrel was still free floating and so all that was needed was to fit a moddy.

A new MAE super short compact was fitted because I like the look, reliabilty, superb noise reduction and stainless steel construction.

This mod was chosen because the most important part is that the rifle had to be used for foxing and lamping so it had to be short. Therefore a barrel length of 19 inches was settled on.

Yes that is short but a quick run through Quickload ballistics (custom case design by me) program and you will find how efficient the 20 PPC is.

Overall length of the rifle with sound moderator fitted is a very handy 44 inches.

See the video here of the first rounds fired:
www.youtube.com


Ballistics

Bullet Weight Powder Velocity fps Energy ft/lbs
Sierra
Blitz King
39gr 26 gr grains of Vit N135 3614 1131


27gr 3733 1207


28 gr 3885 1307







26gr of Hodgdon Benchmark 3655 1157


27gr 3781 1238


28gr 3897 1316










Hornady
V-Max
40gr 25gr of Vit N133 3623 1166


26gr 3710 1223


27gr 3876 1335





Hornady
V-Max
32gr 26 gr grains of Vit N135 3722 985


27gr 3821 1038


28 gr 3978 1125





Berger Varmint Match 40gr 28.5 grains of RL15 powder 3778 1268

All loaded with Federal Match primers.

Field use

It never ceases to amaze me how efficient some cases are even if you do cut the hell out of a barrel. Those velocities are from a 19 inch barrel further proving how good that PPC case is.

This rifle really liked the 39 grain Sierra Blitz Kings that shot bug hole size groups from the off. Watch the video on YouTube https://www.youtube.com/watch?v=HJyRDt9F07U 


A load of only 28grains of Vit N135 powder under a 39 gr Blitz King with and COAL of 52.14mm achieved 3885 fps for 1307 ft/lbs energy. Largest group was 0.5 smallest was five through the same hole!!

Proves to me also that sometimes you do not have to go the full custom rifle route and you can save yourself a lot of cash with a very good Match grade barrel on a standard action like this Sako 75.

Fitted with a NightForce NXS scope and zeroed at 100yards the Quick Target ballistics program was used to generate some down range performance for the 20 PPC/ BlitzKing load with be -0.9 inches low at 200 yds, -5.6 inches low at 300 yds, -15.0 inches at 400 yds and at 500 yards only -31.0 inches.

That’s a great set of ballistic results and makes for a very good fox or long range varmint load in my book.Fitted with a MAE Super Short Compact sound moderator the muzzle report from only 28 grains powder is like a sparrows fart and you can spot every shot as there is zero muzzle lift.

Conclusion

Once again a wildcat cartridge has surprised me into wondering how those ballistics are achievable but the results are the results. Nice thing is it was on a semi custom rifle so in reach of most people and cartridge prep and loading is a doddle. Julian from JMS Arms whose rifle it is can be contacted on 07771 962121 for a similar rifle built and MAE sound moderators and Quickload ballistics program.













Contact

Tel JMS Arms 01444 400126 / 07771 962121




Quickload and QuickTARGET







Monday, 1 September 2014

.17 Fireball, shot down in flames

Introduction


The new Twenty calibres such as the .204 Ruger and 20 Tactical are good illustrations that even after all these years just by tweaking a few dimensions you can still create something new. Remington offer the .17 Remington round a favourite still of mine but now there is the newer .17 Fireball based on a .221 Fireball case.

The parent .221 Fireball case has a small overall length of 1.40 inches and case capacity of just over 23 grains full. Its size and low recoil and noise make it suitable for vermin control in Britain but range is limited to 250 yardish. This fact was not lost on a firm from Las Vegas called Vern O’ Brien rifle company introduced a necked down version of the .221 Fireball case and this was called the .17 Mach IV in the mid sixties.

It’s taken some fifty years for a firm like Remington to realise its true potential and like so many wildcat calibres have legitimised it. To me though it will always be Vern`s old 17 Mach IV round, sorry Remington.

Ballistically the 17 Fireball is efficient and 4000fps with a 20 grain V-Max bullet can be achieved whilst the .17 Remington case can manage 4200 fps. At these speeds the extra velocity is pretty academic really and the Fireballs rationale is that there will be less barrel fouling, less barrel/throat erosion, noise and recoil whilst using less powder consumption.

I had two Fireball rifles both Remington`s, an SPS and a Predator so testing would be interesting and I still remember the days when I shot a .17 Mach IV Contender carbine for hooded crows in Scotland.


Reload choice


I tested bullets from 20 grains up to 30 grains with both hollow point and polymer tip varieties being the preferred choice.

Being a small case with a useable powder capacity when bullet`s seated of just 18-19 grains you can instantly see just how efficient this case is to launch a 20 grain bullet at over 4000 fps! Rather like the .14 Walker Hornet, that only takes 12.5 grains for a 15gr bullet at over 4000fps.

Powders of choice would be on the faster burning side so powders such as IMR 4198, RL 7, RL10X, H4227 or Vit N133 should work.

A special .17 calibre powder funnel helps guide the powder smoothly into the case and I used a precision Harrell powder dispenser that precisely delivers exact powder throws time and again although some may want to weigh each individual charge for accuracy.

Primer wise, I used as a preference Federal Match small primers although CCI were also very consistent.

No real attention to the cases is needed before reloading other than the usual deburring of the neck, cleaning of primer pocket and inside of neck area. Although an internal flash hole deburring is beneficial to consistent ignition and squaring the primer pocket is worth while also.



Bullet Choice

The 20 grain V-Max bullet is perfectly matched to this calibre and remains probably the best .17 bullet design to date in my view.

SPS data and Predator data

Bullet
Weight
Reload data
SPS data
Predator data



Velocity fps Energy ft/lbs Velocity fps Energy ft/lbs
Hornady V-Max 20gr 15.0gr of IMR 4198 powder 3673 fps 599 ft/lbs n/a


15.5gr 3784 fps 636 ft/lbs 3733 fps 619 ft/lbs


16.0gr 3891fps 673 ft/lbs 3856 fps 661 ft/lbs


16.25gr 3952 fps 694 ft/lbs 3900 fps 676 ft/lbs


16.5gr 4003 fps 712 ft/lbs 3911 fps 680 ft/lbs







Hornady V-Max 20gr 14.5gr of Vit N133 powder 3455 fps 524 ft/lbs n/a


15.0gr 3550 fps 560 ft/lbs n/a


15.5gr 3666 fps 809 ft/lbs n/a


16.0gr 3801 fps 642 ft/lbs 3879fps 668ft/lbs







Hornady V-Max 20gr
15.0gr of RL7
powder
3702 fps 609 ft/lbs n/a


15.5gr 3836 fps 654 ft/lbs n/a


16.0gr 3920 fps 683 ft/lbs n/a







Hornady V-Max 20gr 15.0gr of H4227 powder 3953 fps 694 ft/lbs 3911 fps 680 ft/lbs


16.0gr 4044 fps 727 ft/lbs 3987 fps 706 ft/lbs







Hornady V-Max 20gr 17.0gr of Vit N120 4216 fps CAUTION HOT LOAD 790 ft/lbs 4107 fps CAUTION HOT LOAD 749ft/lbs







Berger 25gr 15.0gr of RL 10X 3620 fps 727 ft/lbs n/a


15.5gr 3711 fps 765 ft/lbs 3644 fps 737 ft/lbs


16.0gr 3831 fps 815 ft/lbs 3786 fps 796 ft/lbs


16.5gr 3934 FPS 859 ft/lbs Hot load 3877 fps 835 ft/lbs
Hornady V-Max 25gr 15.0gr of IMR 4198 powder 3771 fps 790 ft/lbs 3724 fps 770ft/lbs


16.0gr 3896 fps 843 ft/lbs 3949 fps 866 ft/lbs














Berger 30gr 14.5gr of Vit N130 powder 3469 fps 801 ft/lbs 3488 fps 811 ft/lbs


15.0gr 3576 fps 852 ft/lbs 3591 fps 859 ft/lbs


15.25gr 3618 fps 872 ft/lbs 3648 fps 887 ft/lbs















Field use

Look at those results, you would think that some were reversed with the longer 26 inch barrel being the higher velocity producer but that 22 incher really performed well, this just goes to show until you shoot a rifle its own idiosyncrasies can only then be found. Tight barrel losses chamber who knows but results are results.

SPS:- The Remington SPS up first, I had on test was a Varmint model with 26 inch barrel. With factory 20grain bullet loads I had 4060fps velocity and 732ft/lbs energy, I was expecting more.

The SPS showed good accuracy with the 16.0 grains of Vit N133 producing 3801fps and 642ft/lbs and 0.85 inch three shots at 100 yard with the 20 gr V-Max.
I switched to 16.5 grains of IMR 4198 powder and now I had 4003 fps and 712 ft/lbs but accuracy was hovering at 1.0 inch.

Now 16.0 grains of RL 7 powder was a consistent load with 0.65-0.75 inch groups at 100 yards with 3920 fps and 683 ft/lbs whilst 15.0gr of H4227 with the 20gr V-Max gave a healthy 3953 fps for 694 ft/lbs and good 0.65 inch groups. I could eke 4044 fps with 16.0gr H4227 but accuracy went to 1.25 inch, interesting.

25 grain Berger`s shot very well with 15.5 gr RL 10X powder, not a top load but nice 0.5 inch groups. Whilst Hornadies 25 grain V-Max bullet sped along at 3896 fps for 843 ft/lbs with payload of 16.0gr of IMR 4198.

30 grain Berger bullets are really a bit large in this case size and velocities reflected this and also I have noticed that Berger’s are a bit tougher than the V-Maxes so penetrate better but do not expand as violently so choice for vermin or fox species will dictate your proper use here.

Predator: - As stated for a short barrel the Predator really shot well it uses a Remington Model Seven action and this design is a blend between the older model M600 and the newer M700 actions that also forms the basis of the solid receiver XR100 action. 
 

With only a 22 inch barrel the factory ammunition was shooting, 4105, 4163, 4150 and 4109 fps for an average of 4147fps and 764ft/lbs energy. Firstly that’s superb velocity from that short barrel in fact better than a 26 inch barrel from the above SPS. Accuracy too was just great, all shots consistently falling between 0.5 -0.75 inches with often three shots less than 0.5 inches. Interestingly enough after five boxes of factory ammunition and cleaning the barrel every second box the velocities actually dropped and stayed lower indicating to me the barrel was running its self in, another important lesson to learn. Figures for the factory ammunition now ran at 3987, 3951, 3981 and 3974fps for an average of 3973 fps and 701 ft/lbs energy, still very impressive.

Reload wise the 20 grain Hornady V-Max bullets and several faster burning powders such as 16.5grains of IMR 4198 producing 3911 fps delivered easily 0.5 inch groups all day, superb.


A very accurate load with shots almost touching at 100 yards was using16.0gr of Vit N133 producing 3879fps and 668ft/lbs and 20gr V-Max bullets.With the 25 grains V-Max bullet a load of 15.0 grains IMR 4198 produces 3724 fps and 770ft/lbs or try 16.5gr of Reloder 10X powder with the Berger for 3877 fps and 835 ft/lbs, again with nice 0.75 inch groups at 100 yards.

But I wanted that elusive 4000fps velocity which I finally achieved with a load of 17.0 grains Vit N120 powder and the 20 grain V-Max to achieve 4107 fps and 749ft/lbs energy with sub 0.5 inch accuracy but it was a hot load so work up to this. I ran this data through the excellent Quickload and QuickTARGET ballistics program. That translates into a trajectory when zeroed at 100 yards of only a drop of -0.9 inches at 200 yards with 378ft/lbs energy remaining and at 300 yards there is drop of -6.0 inches and remaining energy is 262ft/lbs energy so to me that’s its absolute maximum range ideally.

Conclusion

I love the calibre, even when it was called the Mach IV, doh! And I love the fast handling instinctive pointing and lightweight nature of the Predator and also the good accuracy, but the magazine feed needs to be looked at to be utterly reliable. In a rifle like the Predator the all over camouflage coating means there is no fussing with blooded or dirty hands rusting your nice blued barrel. It’s a rifle/calibre combination that will appeal to full time pest controllers and keepers alike. However the .17 Fireball on paper looks just as good as .17 Rem and better than the new .17 Hornet it would seem here in Britain we have not taken it to our hearts as sales have been very slow and I see that Remington supply ammo but not a rifle in that calibre any more, shame.

So really the .17 Fireball would still make a superb vermin calibre for a small light weight custom rifle say built on a small action Tikka or lovely old Sako Vixen or even a full custom Nesika, Stiller or BAT action.


Contact

Tel JMS Arms 01444 400126 / 07771 962121




Quickload and QuickTARGET