by Tom Gaylord, a.k.a. B.B. Pelletier

Part 1

Octane combo
Umarex Octane gas-spring rifle combo.

Just a word
Befoere I get started with today’s report, I want to say something about what happened this weekend. Friday’s airsoft report got a lot of comments. Among them are several questions about the technology of the guns. And some admissions that people didn’t think much of airsoft before they tried it, then they found their opinions changed drastically. That also happened to me, so I can relate to it.

But all you who don’t care for the subject don’t need to worry. This isn’t going to become an airsoft blog. I will continue to report on it at a low level, but I know this is an airgun blog, and that’s not going to change. I want to assure the readers for whom the subject of airsoft is not welcome that we are still going to talk about pellet guns and BBs guns for the most part. I will write a few reports on airsoft now and then, and I trust they won’t upset you too much.

Okay, that’s done. On to the topic of the day!

Today is our second look at the .22-caliber Octane combo from Umarex, and it’s velocity day. Before I get to that, there are a couple adjustments I wanted to make to the rifle. Let’s look at those now.

The first adjustment is the trigger. In the first report, I said the trigger is crisp but heavy. The adjustment screw adjusts only the length of the first-stage pull; so I adjusted it to be longer, and stage 2 decreased. Don’t go too far or the rifle will not cock at all because this adjustment does affect the area of sear contact.

I did go too far and had to call Umarex USA, where I learned that the Octane is supposed to come with a warning tag telling you not to turn in the adjustment screw more than one full turn. I went way past that, so all I had to do was turn the screw back out until the head stood even with the trigger blade — and the trigger was back to working again. For even greater contact, turn the screw so it stands proud of the trigger blade.

Dismantling tip
The second thing I wanted to adjust is the tension on the action forks because the barrel pivot was too loose. To do that, I normally take the barreled action out of the stock. But with this rifle, you need to be aware that the pins in the trigger are not held in and will fall out of the trigger if the action is tipped sideways. I didn’t know this, of course; and when the first pin fell out, it set me up for 45 minutes of work to get the trigger back together again. It seems that the trigger pins are held in place by the stock. Other airguns I’ve worked on have the same arrangement, and one solution is to put tape on one side of the trigger to hold the pins in place…and keep the trigger oriented straight up and down.

Octane combo trigger assembly
Each of the 6 free (not held by circlips or springs) trigger pins seen here is very loose in its hole and will fall out of the trigger if the gun is jostled or tipped to the side. They’re held in place by the stock. What appears to be a pin at the far right is actually a rivet.

Better still — what you can do (VERY CAREFULLY!) is remove both forearm screws and just LOOSEN the rear screw behind the triggerguard. Then the front of the action can be tipped up clear of the stock far enough to tighten the barrel pivot bolt and nut. I would advise against taking the action completely out of the stock. If you do, know how loose the trigger pins are and treat the rifle accordingly. When the pins fall out, the internal trigger parts start moving around. They’re fairly easy to align with their pin holes, except for the safety that takes a little fiddling since it’s a 2-piece assembly with an internal pivot. My advice is to leave the gun in the stock.

One final tip. When you tighten the stock screws, don’t tighten the rear stock screw (the one behind the triggerguard) too much or the trigger won’t function. It was not tight when I first took the action out of the stock; and I found that if I tightened it too much, the trigger would not work. Umarex told me the screw shouldn’t affect the trigger at all, but I’m just reporting on the behavior of my test rifle.

Now, let’s look at the velocity of the Octane. I’ve selected 3 popular lead pellets and one lead-free pellet.

JSB Exact Jumbo
The first pellet I tested was the 15.9-grain JSB Exact Jumbo. This is a popular and very accurate pellet in many airguns, and I think it may be accurate in the Octane. This pellet averaged 762 f.p.s. in the Octane. The low was 748 f.p.s., and the high was 787 f.p.s.; so the spread was 39 f.p.s. At the average velocity, this pellet produced 20.51 foot-pounds of muzzle energy.

This pellet loaded easily, perhaps too easily. I think it might be a little undersized for the Octane’s breech. That could affect the accuracy. We’ll see.

RWS Hobby
The RWS Hobby pellet weighs 11.9 grains in .22 caliber and is very tight in the Octane’s breech. It averaged 889 f.p.s. in the rifle with a low of 867 and a high of 902 f.p.s. So the spread was 35 f.p.s. At the average velocity, this pellet produces 20.89 foot-pounds of energy at the muzzle.

I don’t know how Hobbys will do in the Octane, but I suspect they’ll do well because of the tight fit in the bore. Of course, the Hobby is a wadcutter, so accuracy will fall off after about 25 yards.

Beeman Kodiak
The .22-caliber Beeman Kodiak dome weighs 21.14 grains, which makes it a very heavy pellet. In the Octane, Kodiaks averaged 682 f.p.s. with a range from 665 to 691 f.p.s. That’s a total spread of 26 f.p.s. At the maximum velocity, the Kodiak produces 21.84 foot-pounds at the muzzle.

My guess is that the Kodiak pellet might also be a good one for the Octane. If so, that’s great because it also produces the most energy of all the lead pellets tested.

RWS HyperMAX
Okay, the name of the game with pellet rifles these days is speed, and the RWS HyperMAX lead-free pellet at 9.9 grains is the way to get it. In the Octane, they averaged 1029 f.p.s. with a spread from 1022 to 1075 f.p.s. That’s a spread of 53 f.p.s., so the rifle is probably still burning a lot of fuel. At the average velocity, the HyperMAX pellet produced 23.28 foot-pounds of energy at the muzzle.

The HyperMAX pellet fit the breech very loosely. That’s probably where the extra velocity spread came from, as more dieseling was generated by less pellet resistance. I doubt this pellet will do very well in the Octane because of the loose fit.

Shooting behavior
The rifle recoils noticeably in both directions, but there’s no vibration, whatsoever. Nearly all rifles with gas springs have a sharp buzz that hits you in the cheek, but the Octane doesn’t. In fact, aside from the recoil, it’s a very smooth-shooting spring rifle.

Trigger-pull
Remember that I had to adjust the trigger for a very definite stage-2 let-off. That affected the trigger-pull a lot. I was able to adjust it back to a release of 7 lbs., 14 oz. with very little creep. It’s heavy, as I noted before, but I think it’s crisp enough to do good work. We shall soon see!

The Octane IS NOT LOUD!
When I first tested the rifle it was very loud. And the sound persisted for longer than I felt the dieseling of a new airgun would last. But during this test the rifle suddenly became MUCH quieter. Obviously, it had been dieseling and I didn’t know it.

I originally told Edith it was a 3.7 on the sound scale when I tested it, and she adjusted the loudness level on Pyramyd Air’s product page to 4. But now she can hear that the Octane is clearly a 3. I apologize to everyone who was mislead by my earlier report. The Octane is a normal-sounding breakbarrel air rifle.

Observations thus far.
I said in Part 1 that the Octane holds very well in the hands. The weight is biased forward toward the muzzle, and the stock is slender when the off hand rests. Add the smooth shooting to this, and I think the Octane might surprise us in the accuracy test.

I plan on shooting the rifle at 10 meters with its open sights first. That should give us an idea of which pellets it likes. Then, I’ll mount the scope and shoot those best pellets at 10 meters, again. That does 2 things. First, it confirms the pellets are as good as we think; and second, it allows me time to adjust the scope for the second accuracy test at 25 yards.