The downside is that it also injects stresses into the steel and early hammer-forged barrels got a bad reputation for groups that increased in size and/or bullet impact changes as they heated in use. So, this was something I’d be looking for in my new Armalon barrel. I’ll stress too, that while this all sounds very mechanistic - just bore a blank and feed it into a machine - making high-grade barrels requires a great deal of skill and experience from the machine shop staff just as with any other process. A modern well made example is a very different animal from its ancestors, likewise dirt-cheap assault rifle tubes
77gn Scenar groups. Number 3 at the top was only 0.2” until the 5th and final shot came in low.
MINI PROJECT RIFLE
REMINGTON 700 SPS TACTICAL by Laurie Holland
produced in production runs of thousands – if you own a good CZ, Remington, Steyr, Tikka, or Sako rifle, you have the proof of this.
Another downside is that mandrels are very expensive and can only produce a single rifling form and pitch, so you either have to spend a fortune on mandrels or offer a limited choice of internal specifications. My barrel is made with a 1-7.784 twist-rate which may seem an odd figure when we think of American (or Border Barrels) made 0.224 barrels in 1-7 to 1-14 twist rates, 8, 9 and 12 being the most popular. Actually, it’s 18th Century Bourbon France and its SI (metric) measurements system to blame for this - the twist rate being 1 in 200mm - which suggests that Armalon sources mandrels in Steyr rather than Solihull. Anyway, that’s one turn in eight inches for my purposes.
Clearances
After receiving the barrelled action, two issues now arose. The first and obvious one was that on mating it back with the stock, the much fatter barrel wasn’t fully floating. There was a just right amount of clearance underneath and on the left side of the barrel channel but several inches of metal were in hard contact with the stock on the right side. No great problem, just mill the channel out an eighth of an inch on this side but time was pressing and we wanted to see what the barrel could do.
The good news was that whilst a far from ideal arrangement, the barrel and stock were in good
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