Considering my options- (In .25) Why should I choose the 600mm over the 700mm barrel on the Impact MkII? Anyone have both and can cite velocity or accuracy numbers? Thanks in advance for your replies. hi-vel
Why? FX 600mm .vs. 700mm barrel in .25
- Thread starter hi-vel
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The 700mm nearly always makes 40-50 FPS difference in velocity over the 600mm, I have tried all the calibers 600 VS 700.
Some folks like the fact that you can then reduce the air useage and maintain velocity of the 600 barrel thus getting extra shots.
I prefer as fast as possible personally and with slugs you need all the velocity you can get.
Some folks like the fact that you can then reduce the air useage and maintain velocity of the 600 barrel thus getting extra shots.
I prefer as fast as possible personally and with slugs you need all the velocity you can get.
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The 700 mm will give you increased velocity and the 600 would give you a bit more maneuverability in the brush while hunting. A bit quicker on the draw.
A lot of guys go with the 700 because of the increase in power without an increase in reg pressure and of course higher velocity for slugs at max reg setting. I'm hearing that slug accuracy requires higher speed, up in the mid to high 900 fps range.. I'm not shooting slugs yet so this is from what I have read. If I decide to shoot slugs then I would seriously consider the 700 mm.
I'd imagine the exact velocity increase would vary from gun to gun but I think FX's marketing mentioned 10% increase over the 600. It's around 450 bucks extra if you start with the 600 and decide to get into slugs and find a need for the 700 mm because you'll have to buy the whole barrel set up for the 700.
So my $.02
Hope that helps
KP
A lot of guys go with the 700 because of the increase in power without an increase in reg pressure and of course higher velocity for slugs at max reg setting. I'm hearing that slug accuracy requires higher speed, up in the mid to high 900 fps range.. I'm not shooting slugs yet so this is from what I have read. If I decide to shoot slugs then I would seriously consider the 700 mm.
I'd imagine the exact velocity increase would vary from gun to gun but I think FX's marketing mentioned 10% increase over the 600. It's around 450 bucks extra if you start with the 600 and decide to get into slugs and find a need for the 700 mm because you'll have to buy the whole barrel set up for the 700.
So my $.02
Hope that helps
KP
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If you have tried them, do you find any accuracy edge related to the length? Thanks! hi-vel
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I haven't tried them yet. Wanted to buy one but up until recently they have been out of stock. I also have the pellet liner in 600 mm fo my gen1 Impact. There were no liners when I got my Impact and only 600 mm liners were available when I got my liner so now I'm in the dilemma I mentioned above. I'll have to spring $450 for a 700 mm barrel assembly and slug liner.
I'm sure someone with more hands on will chime in.
KP
I'm sure someone with more hands on will chime in.
KP
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I have an Impact X .25 with 700mm barrel. For the extra $50 Darren from AOA had convinced me it had many benefits... futuristic ones. This is coming true with the slugs and slug liners addition. I have been shooting 33.95gr pellets with quite good FPE/FPS. I don't think you'll attain the same with the 600mm. However, I am not the expert on this, others may know more.
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Besides velocity, the longer the barrel the more forgiving is for tuning errors, the shorter the barrel less forgiving. All are very accurate
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I have the 600mm 25. Max fps I can get from 34gr is 930fps. Thats more than enough to take down any game. Even hogs and coyotes. Imagine a 34gr pellet coming at your face at 930fps. You will go down lol. I get u under .50 inches at 50 yards and 1" at 100 yards. 700mm will give about 30-40 more fps but it will not give you better accuracy. Accuracy is more on the person. Different people shooting the same gun will get different accuracy. Go with whatever you want. If you want short and compact, which the impact is base on aka bullpup design, go for the 600mm. If you want a long gun about same length as a rifle, go with the 700mm. Imo it defeat the purpose of of a bullpup if you just gonna slap on 700mm, 800mm, 900mm barrel on a bullpup.
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The only caveat I have to offer to that regarding the "accuracy" of the 700 vs 600 mm. barrel is that the only way I can get the slugs to give me identical accuracy results to pellets at close range is to get them going between 900-1000 fps. I wasn't able to achieve this velocity with my 600 mm barrel without massively sacrificing air consumption and even then was capped under 930 FPS.
Having owned both, I would take the 700 - but I am not carrying my impact through the woods. I do hunt/pest with it a lot, but I primarily do so from stationary vantage points.
Again, this is my experience only and your mileage may vary.
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I went from 500mm .177 barrel to 700mm when I bought the .25 kit. I find it a litle anoying with the 700mm is that you have to unscrew the moderator to get the gun to fit in the case (I might buy a longer case because of it). If you like to sit in your car and shoot, you can not simply put the gun on the passenger seat, or back seat, and move it around to shoot out the driver side window, as you will most likely bump it into something. I am not a hunter, but I can see the benefit with a shorter barrel in thight spaces. If you like to carry the gun with one hand along your side, you have to be a litle more carefull as the end of the barrel will be closer to the ground. So I can see the benefits of a shorter barrel. Not that I would replace mine though
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Norm and I find no accuracy differences. The speed difference is real.
Also i want to state here that massive speed is not required for slugs. I have made many shots using my 600mm crown at 200 yards slinging 36 gr slugs at 850. Speed helps but is not a prerequisite. A good tune can do a lot.
Also i want to state here that massive speed is not required for slugs. I have made many shots using my 600mm crown at 200 yards slinging 36 gr slugs at 850. Speed helps but is not a prerequisite. A good tune can do a lot.
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I'm shooting a Gen 1 with 600 mm slug liner A and MKII's My latest target and new personal best is 0.365" for three shots at 100y. This after tuning, according to Bob_O's video on that subject. No, not every target is that good but all now are significantly under 1"
I found that the heaviest MKII's work better at 880 fps.
So I'm not real interested in going over to slugs at this point. Maybe later.
One can achieve great results with shorter barrels and heavy pellets with the Impact. Takes a focused approach to tuning.
KP
I found that the heaviest MKII's work better at 880 fps.
So I'm not real interested in going over to slugs at this point. Maybe later.
One can achieve great results with shorter barrels and heavy pellets with the Impact. Takes a focused approach to tuning.
KP
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I just ordered everything to up grade my older 30 cal fx Impact to shoot 25 cal slugs. I included everything recommended by Utah Air Guns to get the most power. I went with the 600mm barrel because it was in stock and the 700 mm was 6 weeks out. I was told to expect 40 to 50 FPS slower just hoping that I can get it dialed in to shoot to 200 yards with Nelson slugs. I have a 30 cal compact Impact that is sub moa at 100 yards and hoping to stretch it out on accasion
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My suggestion go with the 600 especially if you will be adding a moderator. its a bullpup design and the 700 with a moderator makes it as long as a musket.
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I JUST paid for the 600mm today in .25. I went back and fourth so many times wondering which to get. Barrel droop, harmonics, fps, size, bottle size, shot count, so many factors to consider.
People have said the 700mm gets 30ish fps more, but other people have said the 600mm can shoot just as fast with the transfer port and a bored out pellet probe/or slug kit.
I think the biggest benefit of the sniper (700mm) is the larger bottle, which will get 20% or so more shots. As far as distance, I have seen 600mm hit targets at 150 yards away. But how far to you plan to shoot? Realistically?
Bottom line, nothing is set in stone. You can always change the barrels, so why stress about it? You can go from a compact to a 700mm.
People have said the 700mm gets 30ish fps more, but other people have said the 600mm can shoot just as fast with the transfer port and a bored out pellet probe/or slug kit.
I think the biggest benefit of the sniper (700mm) is the larger bottle, which will get 20% or so more shots. As far as distance, I have seen 600mm hit targets at 150 yards away. But how far to you plan to shoot? Realistically?
Bottom line, nothing is set in stone. You can always change the barrels, so why stress about it? You can go from a compact to a 700mm.
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I just recently bought a 600mm and honest wish I had gone with the 700mm the gun is a lot shorter than I thought it would be after using it for a while and the extra 4inches of the 700mm would make a big difference in maneuverability I would rather have the extra velocity personally but I went with the shorter version. I am still happy with it and its a pest control machine.
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I have a 700 25 cal impact mk2 it's about as long as my raw but it's a 28 inch barrel and my raw is only a 24 so you gain some room for the longer barrels it's up to you wether you want extra fps and power which is nice if your going to do slugs my opinion would it wouldn't really matter alot if your going to stick to pellets which you can get plenty of fps for even out of the 500 barrel so just depends on hunting situation and if you want more speed or power
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