Ase Utra SL9i

Since full-bore moderators have become a household item for centrefire rifle shooters, we have seen several different designs and multiple companies producing them come and go. Long, muzzle-mounted cans gave way to the more compact, reflex-types, with their internal expansion chambers that wrapped around the barrel. Equally, materials have changed too, and now include steel, aluminium, and even carbon fibre.

Built to last

Ase Utra has been in this game for a long time and aims its high-quality and innovative products at hunters and professional users alike. On test here is the SL9i, from their S Series, a big and tough design aimed at the powerful .300 Winchester Magnum and .338 Lapua Magnum cartridges, or for that matter, any .30” cal, starting with the .308 Win. At 1.3 lbs, it shows an all-welded construction made from 300 series stainless steel. It’s no lightweight, nor is it meant to be, as the calibres it is designed to handle will attest to. 

Win Mag

My tester was destined for a Bergara B14 HMR Green in .300 Win Mag. With its heavy 26” barrel, the rifle is no lightweight, weighing in at nearly 14 lbs fully bombed up. Once fitted, the SL9i added over a pound up front. But you do get the impression that it’s built to last, certainly when compared to the lighter aluminium models, which, in some cases, trade strength for weight reduction, which cannot be a good recipe for a long life and hard use! 

Noise reduction

I tested the SL9i with factory ammo and some reloads. The former consisted of some RWS Speed Tip Professional (165-grain bullet at 3082 fps | 3479 ft/lbs) and the latter was a load using a 175-grain Sierra Tipped Match King (2763 fps | 2966 ft/lbs). Sound suppression while using a .308 Win cartridge is quoted by Ase Utra at 32–35 dB, with the microphone 1m left of the muzzle. As can be imagined, a .300 Win Mag or .338 Lapua creates a big signature, and when that comes out of the muzzle unmoderated, it needs a lot of taming. 

Mk 1 ear

I have no sound measuring systems and use my Mk 1 ear to judge how effective a moddy is, as you tend to get a pressure wave (spike) which can be loud enough to hurt in the inner ear, indicating that the mod isn’t doing the job properly, regardless of big or small cartridges. OK, you might think caveman thinking, but it is a physical gauge of any design.

For comparison, I had an aluminium Haukson reflex unit that came with the rifle. Moderation was effective with both cans, with the SL9i seeming to deaden the report a bit more than the lighter, aluminium model, which sounded higher and snappier. Also, the heavier Ase Utra gave a bit more recoil control, doubtless due to its extra weight.

For me, the real difference is that the build of the SL9i will doubtless take the pounding of heavy magnum loads for serious, long-term use, better than a lighter alloy design, which is probably more hunting-orientated. So it’s your call!