BSA R10 MK2 precharged repeater: Part 3

by Tom Gaylord
Writing as B.B. Pelletier

BSA R10 Mk2
BSA’s Mark 2 repeater has a rubber-covered beechwood stock.

Part 1
Part 2

This report covers:

  • Setup|
  • The test
  • Sight in
  • H&N Baracuda Match with 4.50mm head
  • The trigger
  • H&N Sniper Magnum
  • JSB Exact Heavy 
  • Crosman Premier Heavy
  • Discussion
  • Sound test
  • Summary

Today we look at the accuracy of the .177-caliber BSA R10 MK2 precharged repeater. A lot of folks swear by these rifles, so I’m hoping for the best.


The R1 has no sights, so a scope is needed. To give it the best chance I could, I mounted a Meopta MeoPro Optika6 3-18X56 scope. It’s the best scope I own and will give the R10 its best chance to excel. The scope is mounted in Sportsmatch Fully Adjustable Scope Rings, so I can change it while it’s mounted to the rifle. That’s a big time-saver for me! The mounts are quite expensive, but for testing purposes they’re ideal!

The test

I will shoot from 25 yards today. And all groups will be 10-shot groups. I’m shooting off a sandbag rest to keep the rifle as stable as possible.

Sight in

The scope mounted quickly on the 11mm scope rail. I shot once at 12 feet and the pellet was in the bull, so I backed up to 25 yards and shot again. The pellet was now hitting high and slightly right, so I adjusted it down (a lot) and to the left. I didn’t want pellets striking the dot in the center of the bull, as that was my aim point, so I adjusted them to strike to the left of center and slightly high. This Meopta scope is so clear that I can see the dot at the center of the reticle which is about the same size as the 10-dot on the bull at 25 yards.

H&N Baracuda Match with 4.50mm head

First to be tested was the H&N Baracuda Match with a 4.50mm head. This was also the pellet I used to sight in. Ten pellets made a group measuring 0.346-inches between centers at 25 yards. The group is reasonably round and I’m satisfied with it.

R10 Baracuda Match group
The BSA R10 put 10 H&N Baracuda Match pellets into a nice round 0.346-inch group at 25 yards.

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The trigger

Remember that I adjusted the trigger in Part 2? It’s holding pretty well, though once or twice as I shot I did feel a touch of creep in the stage-two pull. And, when you’re shooting for accuracy is when you notice the trigger the most. You can’t always tell until this stage of the testing, but here everything becomes crystal clear.

H&N Sniper Magnum

Next to be tested was the H&N Sniper Magnum pellet. In .177 this pellet is very heavy, at 15 grains, but the same pellet in .22 caliber is on the heavier side of medium, at 17.9 grains. I mention that only because I find it odd.

Eight of ten Sniper Magnum pellets went into 0.417-inches at 25 yards, but two shots went wide. There was no called pull, either. The 10-shot group measures 1.508-inches between centers.

R10 Sniper Magnum group
Ten H&N Sniper Magnums went into 1.508-inches at 25 yards, but eight are in 0.417-inches. The two wide shots were not called pulls.

JSB Exact Heavy 

The next pellet I shot was the 10.34-grain JSB Exact Heavy dome. Ten of them went into a 0.40-inch group at 25 yards. It’s not as round a group as I’d like, but it’s fairly tight.

R10 Exact Heavy group
Ten JSB Exact Heavys made a tight group measuring 0.40-inches at 25 yards.

Crosman Premier Heavy

The last pellet I tested in the R10 was the 10.5-grain Crosman Premier Heavy. Before I shot it I adjusted the scope three clicks to the right, only because I was tired of seeing them all go to the left.

I didn’t know what to expect from this hard pellet, but I was pleasantly surprised. Ten Premiers went into 0.395-inches at 25 yards.

R10 Premier Heavy group
Ten Crosman Premier Heavy pellets went into 0.395-inches at 25 yards.


Three of the four pellets I tested today gave very good groups at 25 yards. I had hoped to see a trime or a gold dollar used for comparison with some of the groups, but I guess that wasn’t to be. I will say that the Meopta scope is so clear that I know beyond a doubt that each shot was as good as I could make it.

Sound test

Next, we try something for reader Henry_Texas, who asked to see the difference between the sound a heavy pellet makes in the silenced rifle and the sound a lightweight pellet makes. The difference will be the breaking of the sound barrier.

I’ll test both a heavy and a light pellet today, as the air pressure and humidity affect where the sound barrier is. So my numbers from Part 2 aren’t as accurate. Or at least that’s what I’m telling myself.

The rifle has the silencer installed. That makes a big difference.

The first shot was a 10.65-grain Baracuda Match pellet. It registered 82.5 dB on the C scale of the sound meter.

R10 heavy pellet discharge
A heavy H&N Baracuda Match pellet registered 82.5 dB on the C scale of the sound meter.

Next to be fired was an RWS Hobby pellet. It registered 92.3 dB on the C scale of the sound meter.

R10 light pellet discharge
The R10 shot an RWS Hobby pellet out at 92.3 dB on the C scale of the sound meter.

That’s the difference between a pellet that’s below the sound barrier and one that’s above. The lighter one cannot be entirely silenced. 


That’s it for today. This was a run-up for the 50-yard test that’s yet to come.

39 thoughts on “BSA R10 MK2 precharged repeater: Part 3”

  1. B.B.,

    First, I never knew you could reload a rim fire cartridge. Maybe you couldn’t last time I looked, which was only decades ago.
    Second, with the Origin I have a PCP in all three of the most used small calibers. It looks like a keeper, for me at least.
    I have travelled to the dark side and will only look back when it is necessary. I do want a decent multipump, though.

    Arlene is still in hospital, but there is hope so hopefully not much longer.

    Have a blessed Christmas, all.


  2. BB,

    That ain’t too bad. Since it is yours, perhaps you should work in some more time with it when you can and try to find THE pellet for it. Maybe a RWS Super Dome or Super H-Point. Sometimes the “odd” pellet clicks.

    My Gamo CFX liked H&N Field Target Trophy in 4.51mm head. It did not like them in 4.50mm or 4.52mm. You might try different head sizes with the Baracuda Match which seemed to be doing pretty good there.

    I am afraid I just do not like that coated stock.

    That Sam I am, that Sam I am!
    I do not like green eggs and ham!

  3. BB, that’s a real nice $300. airgun. That’s about what I paid for my ‘refurb’ Mrod 10 years ago. Thanks Stephen Archer! The thing about an unsupported shroud is you need some way to align the bore with the silencer/moderator. They usually put a plastic part on the end of the barrel with an oring on it to insure that it is aligned, but the barrel is not free floated now, and the oring needs to lubed so it always returns to it’s neutral position inside the shroud. I got rid of that plastic piece on the end of the barrel, and tapped and threaded little allen screws into the barrel band, whichs allows me to keep my free floated barrel, but makes a rigid and adjustable shroud. It’s more of a pain in the butt, I can lean the gun against the wall, and I know it wont affect my barrel. Your mileage may vary. Nice shooting Sir.

  4. Thanks BB for the ‘speed-sound’ test. It confirms what many of us have heard when testing lighter pellets in powerful rifles. Now we have figures to quantify it, and those 10 dB of difference are quite significant.

    Another interesting, if not totally surprising, result is that the average sound is lower with the supersonic pellet by a smaller but noticeable 3 dB. That suggests that the supersonic pellet makes more of a sharp and loud ‘crack’ compared to a longer and milder ‘boom’ of the slower pellet. The amount of acoustic energy is probably similar, just the slow and long one reaches a lower peak.

    By the way, both values are below the ear damage threshold. That said, ear protection is a good thing when in doubt.


  5. Kenholmz,
    Good luck with Arlene. I know what you are going through. My wife Sylva has been in hospital for ten days and will be most likely for maybe two more weeks and then rehab. I’m lucky that my three sons live in the Austin, Texas area and I can stay with them so I can see her everyday.
    As far as I am concerned, 2020 stinks. Virus and now hospital.

  6. I found something out today. And maybe he might not want me to post but I see it no other way but to.

    And I don’t even know if he still reads the blog.

    Dave with the RAI componants broke his back at work a while back.

    He tells me he is making it. I’m not sure of details other than he is suppose to be starting therapy. But if anything I figured we can pray for him.

    BB maybe you can give him a holler and see if he is ok. Hope I’m not going in a place I shouldn’t of on the blog.

  7. Yesterday I posted a picture that showed a .25 caliber rimfire round. I am pretty sure it is a .25 Steven’s round. I vaguely remember my dad telling me he had a .25 Stevens rifle that he liked. Wonder what happened to it.


      • That would be great. He had a few guns in odd places, but none I did not know about. As soon as i was old enough I got the job of cleaning and oiling the all the guns every few months even if they were not shot. I still have all of my mother’s and father’s guns, a couple are worn out but I will pass them down the line.

        I see the .25 Stevens Favorite was $5.00 in the 1903 Sears catalog.

  8. BB,

    I shot the Origin at 10 yards just to get shots on a target. I took the scope off of a Marauder a while back. I read amazed at how far off it was laterally.
    I shot at 30 yards and refined my aim.
    In all I shot 40 Benjamin 22 call up pellets.
    Today, I shot 10 at 40 yrs. The photo tells the story. I take credit for every shot; there were no fliers. My shooting was somewhat unstable. All 10 shots were done on lowest magnification.
    It looks promising


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