If anyone would like a look at the review I've done on the rifle here it is:
I recently decided to move from 17Rem to a different calibre. After some thought and consideration I looked at a few different options. My requirements for this rifle were as follows: long barrel life, good ballistics (for longer ranges shots) , efficiency (low powder consumption) and good hitting power for fox control. I shoot hundreds of rabbits and many corvids per year at ranges of 50-500 yards with my smaller calibre CF rifle so all the above were important factors. I decided that .223 or .223AI would fit the bill nicely (along with .22BR). I was swayed to the Ackley as it looked a sexy case and I fancied trying something new. The 40' shoulder and almost parallel case wall got my juices flowing. I sourced a 223AI reamer that had the correct lead to allow the 50-55g bullets to be seated at the optimum level (just above the shoulder/neck junction) and be close to the lands giving me the option of seating in or off the lands. I then bought a Pacnor 1:12 twist #5 contour barrel from Neil McKillop. Dave Folwell from Bowtec Custom Rifles did the smithing for me and an impressive job he did. I specified the pacnor to be finished at 22" with a 1/2" UNF to match my existing mod. Dave bored out my excellent 17 cal DM80 to 6.7mm to allow adequate clearance for the .224 bullets. Meanwhile I bought my loading ingredients which included Redding S Type NS bushing die set with competition seater, N133, 205M primers and 53g Vmax.
The rifle came back perfectly finished with both barrel and action bead-blasted plus it was all nicely wrapped in bubble wrap (good to see the smith taking care of my pride and joy). Machining was neat and clean as always from Dave.
The next day I was out to test the fireforming loads. It was pleasing to see how effortlessly the cases formed along with very accurate grouping.
The load development
I've seen on different forums that people have found the fireforming loads to be very accurate and I have to say I agree. I shot 6 groups of different charge weights 4 of which were below 0.25 MOA and the other 2 around the 0.5 MOA. I knew then this rifle had very good accuracy potential. Velocity for the fireforming loads was between 3150-3340 with loads of N133 between 23.5-24.5 using 53g vmax seated just into the lands at an OAL of 1.904" to the ogive and using Lapua cases.
I decided on 24.5g to fireform the rest of the new cases.
After shooting the remaining fireforming rounds at corvids, rabbits etc I knew that I had far from wasted barrel life and rounds during this process. The next stage was to test the AI loads. I made up charges from 25.2-26.4 and used the same OAL as the FF loads. Although not all groups were super accurate they exhibited a stable POI which always gives me confidence in the load with respect to consistency. Velocity was 3380-3570 fps for the charges tested. I deduced that 26.2 was the OCW (optimum charge weight) and thought I would shoot that for a while and see how it faired at longer ranges and as the barrel slicked up etc.
See targets below:
Bedding
My barrels have never sat perfectly central in this standard stock so I knew that soon I would be bedding it to centralise it. The new barrel actually was able to touch the left side of the forend due to being slightly wider. It was the perfect excuse to start hacking it to bits with the dremmel, throw in some acragel and create that perfect stock/action bond. So I bedded the action and the first inch of the barrel tenon. I then tested the POI and refined the zero the requiring only a minor adjustment.
Case sizing and feeding
I have been using Redding S Type NS bushing and competition seater dies. On the 3rd load I noticed that the rounds did not feed as well and were hanging up In the chamber when bolted slowly. I bought a metal 5 shot mag from Sean at Litt's as I knew it would be another aspect to tune regarding feeding as all other possibilities had been done already for example chamber entrance radiused, feed ramp angle altered and polished and it still did not feed flawlessly. The retaining lips on the metal 5 shot Tikka mags allow manipulation for better feeding but at this stage the use of the metal 6 shot was enough to allow smooth feeding of the AI rounds. I later tried to adjust the retaining lips to improve feeding with slow bolt operation but it did not help. Since then I have developed the technique for positive feeding. The trick is to keep the bolt moving fairly swiftly which doesn't give the case chance to drop down at the back and jam the bolt.
Further testing
After a few vermin shooting sessions and being aware that the barrel and cases would be fully settled in I decided to revisit the targets and test FL sized (using the body die and NS die) vs NS only rounds. It was reassuring to see that there was no discernible difference in POI, velocity or accuracy between the 2 variations. This means that I can FL when I want without the worry of wondering whether the load has altered or POI shifted etc.
Both case prep techniques were giving a consistent 0.25-0.28 MOA.
I have given the rifle a few good work outs in the field recently. This can be seen in the video.
Any queries please contact me at si-snipe@hotmail.com
