Eun Jin Sumatra 2500 Carbine Review in .25 caliber

The Sam Yang or Eun Jin Sumatra Carbine is an interesting lever action Korean PCP or Pre-charged Pneumatic air gun. It’s compact, powerful, and accurate. Though the aesthetics of the rifle might chase some away with it’s woodland scene embossed on the metal covering the receiver, the performance of the airgun is likely to convert some, and allow them to ignore the aesthetics. I have decided to purchase this Sumatra Carbine, review it and the Hill Pump, and share my experience.

The Sumatra 2500 Carbine in .25 is ordered along with a Hill Pump and a bunch of different .25 pellets. Will shoot still images and perhaps video of the unboxing, and do a substantial review, including accuracy and chronograph results.

And now I wait.

This is what it going to look like.

Update on the Sumatra Carbine Review

It’s here! Came home to find a large box sitting in next to the front door. I tried to be patient, but it wasn’t a minute before I thought, screw that, let me at it!

Here’s some unboxing images of the Sumatra

The Sumatra 2500 Carbine .25 is made by the South Korean Company Eun Jin a subsidiary of Sam Yang Industries. The South Koreans are known for making unique large caliber and hard hitting PCP air guns.

Update on the Sam Yang Sumatra Carbine Review:

I’ve yet to spend much quality time with my new Sumatra Carbine. Been too busy working, commuting and doing a ton of other stuff. But the little time I have spent, I’ve learned a few things and have a few observations.

First, the Sumatra and the Hill Pump shout QUALITY. Fit and finish of both are superb.

The Sumatra has very nice looking wood with a grain that to me looks like Mahogany. What it really is I have no idea.

When I first saw a Sumatra a few years ago, I thought they looked kind of cheap, and to be honest I did not like the embossed metal with the woodland scene. And I was dubious of the cocking mechanism. But upon actually seeing the gun, and putting it through a few cycles of dry firing, and few live firing with some pellets, I am impressed. I like it. It looks and feels substantial. The cocking is smooth but a tad stiff. I suspect after a few hundred rounds or more it will loosen up, and get used to me, and I’ll get used to it. I think tools eventually take on the history and experience of the owner, and become rather personalized. For this reason I tend to keep and use my tools for a long time. In this case the tool is the Sumatra.

The Sumatra is so pristine now, I’m almost afraid of using it for fear of the first mark, scar or ding. I know it will come, and it will smart for a while, but eventually I’ll get over it, and that beautiful work of engineering and sculpture will start to show a bit of age and history. I think this is good.

Weight of the Sumatra without scope is somewhere in the neighborhood of 6 or 6 1/2 pounds. To me the balance of the gun is very good, and I can see many happy trips into the wild with this slung over my shoulder and not getting tired because it weighs ten or twelve pounds or is extremely front weighted. Huge user friendly weight and balance. I’m pleased.

I will be installing a scope. Which one, I’m not entirely sure of yet. I’m going to try my Leapers Bug Buster and see how that feels. I like the compactness and weight of the Bug Buster, though it could use a side focus knob. Some of the other scopes that are in my list are roughly double the weight, and longer. I’m afraid a heavier scope is going to mess up the balance and make the weight no longer a pleasant experience. But we’ll see.

One thing has me confused, and that is the power adjusting wheel of the Sumatra Carbine. You have a Big Red Dot on one side, Medium sized Green Dot, and Smaller Black Dot. As I understand it, you are supposed to turn the wheel toward the Big Red Dot to increase power, and toward the Small Black Dot to decrease power. More power equals fewer shots before needing to pump up the Sumatra, and Less power equals more shots you get before needing to pump. Simple yes? Funny thing is the wheel turns way beyond the scale, and on the wheel itself you have an additional set of small red, green and black dots. Reading up on the subject, some folks say to leave the cocking lever open while adjusting the power wheel. (to be explored further when I actually get a chance to spend more time with the carbine). Later: the lever must be open for the power adjustment to work. Without the lever open, you can turn the power adjuster, and have no effect what so ever.

The Sumatra came in a box labeled with Air Venturi’s name, who I think is the company who imports the Sam Yang / Eun Jin Sumatra Carbine. The box has several models pictured on the front of the box, which means the box is used for several different Sam Yang Air Rifles. This is fine. But upon opening the box and laying eyes on the rifle for the first time, I see that Air Venturi has taken the privilege of embossing or engraving their name on the top of the receiver of the rifle. Since Air Venturi doesn’t actually appear to manufacture the Sumatra Carbine or any of the Sam Yang air guns, I wonder where they get off on putting their name on something they did not make. I don’t like it, not one bit.

Finally got in some shooting. This rifle is the most accurate air rifle I own, and certainly more accurate than I am much of the time.

I’ve really been enjoying the Sumatra Carbine. I’ve experimented with a variety of pellets, and so far the only it really doesn’t care for is the Eun Jin 35.8 grain pellet. And even it isn’t that bad. I’ve shot decent groups at 12 meters and up to about 80 feet. I have too many neighbors to go beyond that, but I hope to try some 50, 75 and 100 yard shooting soon.

I typically am getting 16 shots at mid power before I need to fill up the gun again. With the Hill pump this typically takes about 80 pumps going from 100 to 200 bar give or take. Not bad and it’s good for strengthening my arms and shoulders.

Knockdown Power of the Sumatra Carbine

The Sumatra run at full power will push most if not all of the pellets I have through a 2×4 fir or redwood board with ease at close distances. Further out you will end up with less of that brute force, but I’d be confident in the heavier Eun Jin Pellet punching through a rabbit, raccoon, possum, wild turkey, ground hog, and small wild hogs. Key with air gun of course is accurate placement of the pellet.

Loudness of the Sumatra

Having read a lot about the Sumatra, one thing that others have said is absolutely true. The Sumatra Carbine in .25 caliber is LOUD! I fired a few times in my backyard at full power, and the air gun sounds like a rim fire or larger firearm. Holy Cow! This rifle is not at all backyard friendly. Beware. I’d like to order up a LDC or Lead Dust Collector to tame the sound volume, but with American laws being unclear about the legality of such a noise suppressor, I am a bit undecided on what to do. For now I’ve turned the rifle down to low power, and limit my backyard plinking.

Defects on My First Sumatra

After living with the Sumatra for a week I discovered several defects. The first defect was a cartridge that did not fit the rifle correctly. I measured the height of both cartridges the rife came with and they are substantially different. The second cartridge packed away in a plastic bag, looked oxidized and shop worn which made me think that this rifle had perhaps been and open box rifle.

The second defect was a chunk of metal missing from the receiver where the indexing pin slides in and out. The metal here is too thin. I wonder exactly what the factory is thinking about the tolerances on this gun. The metal to the side of this pin on one corner is very minimal, and I suspect that many Sumatra Carbines and the full sized rifle suffer from this minuscule amount of metal, and most likely show missing chunks also.

The third defect was two hairline cracks of the stock where it meets the receiver. They are subtle but knowing wood, will continue to lengthen and widen.

Three defects disturbed me and so I returned the rifle to the retail establishment for exchange. That was not a hassle, as they sent me a Fed-ex tag, and it was painless to return. However the rifle was now on backorder and it ended up taking over a month to get back in stock.

More to come…