I have just done some work with Trailboss powder in my .222 and thought I would share.
I do a lot of reloading and I read quite a lot on the subject of Ballistics and I always read about people not being able to stabilize a heavy or longer projectile, yes a long VLD projectile is just as hard to stabilize as a heavy one. Quite often someone will mention projectiles "keyholing" or worse not even making the target. Have you ever wondered what an unstable projectile looks like, or rather what the hole it makes in a target looks like? Well wonder no more here is a perfect example for you to look at. The elliptical holes made by unstable projectiles in the target bellow are quite obvious.
Keyholes marked in Red and Orange, Stabilized group in Green.
At the present I do not own a .22RF so I have been working on a load in my .222 Rem that equates the ballistics of a .22RF for shooting rabbits on a local property. As you can see it takes some trial and error as the lower velocity does not want to stabilize the 50 grain projectiles. This particular target has a nice 5 shot group indicated by the green arrow that was shot with my standard velocity load of a 55 grain boat tail soft point at an even 3000fps. The key holes were shot with a range of projectiles varying in weight from 50 to 55 grains over a charge of 5 grains of Trailboss powder.
Now that I know they are not stabilized I can do one of two things, I can try a lower weight projectile like a 45 or even 40 grains or I can try working up the powder charge to increase the velocity. Ideally I would like to minimize the range of projectiles I need to purchase so I will be working up the powder charge slowly to see if the 50 grain projectiles will stabilize. If that is unsuccessful I will have to try a lower weight projectile and see if that helps.
Now here is the really hard part, I want to tailor the load to land at as close to the same point of impact at 50mts as my standard load as possible.
After another day at the range I managed to get both the 50 and 55 grain projectiles to stabilize and shoot reasonably accurately. As I thought the 55 grain projectiles stabilized at a slightly slower velocity than the 50 grain projectiles due to their shorter design, It took an extra grain of powder to drive the 50 grain projectiles fast enough to stabilize, for this load the 55 grain projectiles liked a charge of 6.5 grains of Trailboss Powder and 50 grain projectiles liked a charge of 7 grains. All that remains is to play with the seating depth a little to tighten up the groups, the following photos show the results.
The 55 grain projectiles seem to like a charge of 6 to 6.5 grains of powder.
The 50 grain projectiles like a charge of 7 grains of powder.
I have also managed to get my hands on a packet of 45 grain projectiles so I will have a play with them and see what I can do. I have a feeling they will be ok over about 5.5 grains of powder, but we will just have to wait and see.
Well I can now confirm Sierra 45 grain soft points shoot very well over 5.5 grains of Trailboss powder in my Howa .222 Rem. I loaded up 20 bullets and had a quick range session this morning. I shot 4 X 5 shot groups at 50 meters and had some very good results.
This initial accuracy held for the first 2 groups then fell off for the third.
As you can see the 3rd group was not all that good, a quick pull through soon had things fixed though.
The final 5 shot group with the projectile for scale,
The accuracy started to fall off after the first 2 groups but a quick pull through with the Boresnake had things back on track for the 4th group. All groups were to the left of center due to a very strong cross wind but vertical dispersion was excellent. Needless to say I have found my light load for shooting rabbits with my .222.
Mule deer and Colorado elk seasons almost done! Hunters driving farm roads, looking for racks, their PH driving them along, I ask that you not pull into my drive. The buck behind me, on the boundary line of the GMU somehow knows. The hunter laughs, I would invite you in to see my Searcy rifles but social distancing prevails, darkness arrives and the buck slides away into secret tree grove...