Whiscombe rifles and barrel harmonics - Part 3
by B.B. Pelletier
I'll try to finish the intro with this post. Several of you have asked about the Whiscombe price and availability. John Whiscombe supposedly stopped building new guns several years ago, but his site is still up. If you read it, it looks like he still makes them, but the last post was in 2003. Mac-1 Airguns sold them for many years but the guns are no longer on their website, as far as I can determine. Pelaire also sold them, but they stopped before 2003. To the best of my knowledge, Whiscombe rifles are no longer being made. If anyone learns differently, please direct me to the website by posting a comment on this blog.
As it turned out, I bought the next to last JW75 made. Most of Whiscombe's customers wanted fixed-barrel rifles, so the JW80 replaced the 75 in the last few years. My rifle came with all four barrels, as I mentioned last time, but I didn't tell you that all four of them are set up for Whiscombe's Harmonic Optimization Tuning System or HOTS. It's an adjustable weight at the muzzle to allow the shooter to "tune" the barrel harmonics to the pellets being used, which is why this blog also addresses barrel harmonics. We will spend more time with the HOTS in the future. My rifle, ordered in 1996 with a thumbhole stock in Grade III walnut, came to $2,350 for everything.
The silver weight can be screwed in or out, changing the barrel vibration harmonics. It's an adaptation of the Browning BOSS that has been used successfully for decades.
When you change pellets or calibers (which means a different barrel), the HOTS has to be retuned. If you think about all the possible combinations, you'll see what a daunting task this can be! That's why it's best to stick with one good pellet per caliber and to index the HOTS weight for that. I haven't done this yet, so I'll use the testing I do for you to establish that for this rifle.
To demonstrate the rifle's potential, I shot a few groups with .177 Beeman Kodiaks at 35 yards. I have no idea if these are the best pellets for the .177 barrel. Of course, the HOTS has yet to be adjusted. The results were close to the best you would get from a TX200, but not quite at the PCP level, which this rifle is capable of. I haven't had much experience with the .177 barrel, either.
At 35 yards, this group of five Kodiaks is good for a spring gun but not quite up to precharged levels. The rifle needs to be tested to find the best pellet for this caliber, then the HOTS needs to be adjusted.
Drawback of the breakbarrel
The barrel has to clear the scope, and that is the biggest drawback to the breakbarrel model. A benefit, of course, is that the breakbarrel is easier to load. I have a 3-12x Simmons on the gun, and it works well, but I cannot mount the Leapers 8-32x that I'd really like to have. The rifle is accurate enough to warrant it.
Trigger and safety
The Whiscombe's trigger is fully adjustable and every bit as nice as any you would find on a premium PCP. The length of the first stage is adjustable, as is the sear engagement and the pull-weight of the second stage. There is also an overtravel adjustment. Despite having to restrain several hundred pounds of force, the trigger is both light and crisp. The automatic safety is a button on top of the receiver that moves back when the rifle is cocked. If the safety hasn't set, the rifle may not be fully cocked. I had a few occurrences with that when I was first learning about the gun. Once taken off, the safety cannot be easily reset.
Worse than a dry-fire
I told you how bad a dry-fire is, but there is something even worse. If you load the rifle first and then cock the pistons, you create a vacuum in the compression chamber. The pellet blocks the air from entering. If you shoot, the pistons are drawn together by the force of both springs and the vacuum between them. That will destroy the rifle.
I could have gotten an adjustable cheekrest on the rifle; since the buttpad adjusts up and down, I figured a movable cheekrest was superfluous. It's already high enough for scope use.
Well, that's the intro. In the coming months, I'll use the Whiscombe to demonstrate a number of classic airgun facts, including the accuracy benefit, if any, of harmonic tuning.