This is a fair statement by Trinity. We have on multiple posts, stated that we don't stand by any promises that this barrel will work optimally on other markers. We have been working to integrate this barrel on the SAR. Although the barrel is a critical part to any marker, many overlook the science of the valve decompression (IE Valve dwell, displacement, laminar or turbulent air flow.) The SR1 has a completely different "engine" from that of the SAR12. Most markers can run a 4-6 inch barrel and produce 300 fps shots...the SAR12 bolt action can't. The bolt action needs every bit of a 14" barrel to be able to reach 300 fps. This is because we have optimized around the 20"
In closing, I will state that we have tested both the HH14 (16 with tip) and the 20". If we didn't see improvements by using the 20" we wouldn't offer it. It is a very expensive barrel to produce. The barrels are heavy, however; we have balanced the SAR12 to use the long heavy barrel. Center of gravity for the SAR12 is in the center of the magazine well, directly between the trigger grip and the offhand hold.