I took a trip down to Bisley today in order to run a barrel break in on the .260Rem and do a little load testing. Although the weather was pretty awful the day proved fruitful and results were very impressive. You may have read the previous Presicion Rifle article which featured Mik Maksimovic at Dolphin gun installing a Trueflite match grade barrel. This was the rifles first outing so I was pretty excited to see how it would work out.
One thing you need to know if you are in the UK and considering the .260Rem option is that there is no decent factory ammunition available. You need to reload or forget about it. I tend to reload anyway so it really made no odds to me. I picked up some Forster .260Rem dies and set about sourcing some components.
Lapua .260Rem Brass
Lapua 139gr 6.5mm Scenars
CCI 200 Large rifle primers
Reload Swiss RS60 Powder.
We have been trialling the Reload Swiss range and thus far been impressed. It produced superb results in the .308. The RS60 is from what I understand Reloader 17. I have been told that by various knowledgeable sources but do not know enough about propellant companies and their dealings to give an opinion. The only load data I could locate (other than internet forum recommended loads for R17) was the user data uploaded on Reload Swiss’s site. It listed 41gr as an accurate load. This seemed to tie in with Alliants 41gr recommendation for R17.. Anyway I figured play safe and began with a load 2 grains below at 39. I stepped up charge weights after that in .2 grain increments. The cartridge overall length (COAL) was 2.833.
Environment and Weather.
I drove up with friends Sam and Les and the weather seemed to be holding out well. Once we arrived at the range the rain began to set in and did not leave. We were luckily undercover. Temperature was mild for this time of year at around 50f and pressure was reading around 29.97inHg. Winds were a light full value right to left.
I prefer to load test from prone however that would mean getting wet. I opted for a bench instead. I shot off a Harris bipod and rear squeeze bag which is my usual preference. The only thing missing was a chrono. Sams faithful Chrono had spewed garbled data previously so unfortunately that is now something we need to sort out..
The barrel break in and load test.
Getting the rifle and cleaning kit ready for the session. I usually sort through all my kit the night before a shoot.
I have not been a huge fan of running barrel break in sessions in the past but I also know that Gunsmiths like Mik know more than me. Mik suggested 5 rounds and clean followed by 10 rounds and clean. Break in complete. I followed his advice and began to run the lightest loads through followed by patches as directed. I am going to clean the gun using only M-pro7 products from day 1 so I can bring you a thorough review of their tactical cleaning kit early next year.
The first shot went about 10″ high, and with 2 more I had set the zero stop on the Vortex PST. Another 2 shots and I knew this rifle was something special.. The aiming dot was .75″ and the first 3 shots that hit were all within the border.
After the cleaning cycle I immediately began increasing charge weight, stepping up to 39.5gr and then up in .2gr increments. Results were a lot better that expected. The groups were pretty much all sub 0.5moa with charge weights around 41gr showing greatest promise. The recoil felt very manageable and the rifle was both an ease and a pleasure to shoot.
Sorry about the messy target. Horrid conditions combined with people peppering my targets (the white patches..)
It was a hard job pulling the best group out of that bunch as Miks work along with the Trueflite barrel produced great groups throughout the range. It would have been ideal to run the test at 200yds to open the groups up a little. I will note that for the COAL variation test early next year. That being said I achieved the expected result – the data concurred with factory recommended load. The COAL I used for these was based upon the standard length I use for Accuracy International .308 mags (2.833″). For some reason it always worked well as a mag length load for .308 and I just stuck with it. I have no doubt that a longer COAL would give improved accuracy but obviously you are then single loading.
I will be replicating the 41gr load and running it at long range on steels in January at which point I will update you all on the results. I will also try and sort a decent Chrono out for the next batch of load testing.
Dolphin Gun Company – www.dolphinguncompany.co.uk
Trueflite Barrels – www.truefliteriflebarrels.co.nz
MDT Stock – http://mdttac.ca
Reload Swiss Propellants – www.reload-swiss.com
M-Pro7 cleaning equipment –www.mpro7.com