GTA
All Springer/NP/PCP Air Gun Discussion General => European/Asian Air Gun Gates => German AirGun Gate => Topic started by: UnderPressure on March 08, 2023, 12:39:56 AM
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I really like the improvements put into the Diana 34 EMS so I got to wondering how long till we see a Diana 350 Magnum EMS?
I am particularly looking forward to the use of the EMS system by Diana to optimize power and accuracy to specific pellet and slug weights.
For example, we know that heavier pellets like less rifling twist than shorter pellets of the same caliber. This because the longer pellets often have longer flares and thus benefit more from flare stabilization than shorter pellets:
RTI with the Prophet (PCP airgun) proved this in competition (Winning Extreme benchrest 2019 at 50 yards) by matching .22 JSB Monster redesigned with a then unheard of twist rate of 1 in 32" in a polygon Lothar Walther barrel.
At 1:47 into the video linked below the twist rate of 1 in 32" is mentioned:
https://youtu.be/UIMaQjG8l8w
Review of that rifle by HAM below:
https://hardairmagazine.com/reviews/rti-prophet-test-review-22-caliber/
Notice the accuracy was indeed best with the heaviest and longest pellet, the JSB Monster redesigned.
So building on the idea of slower twist rates for long fast pellets it would be good to have a Diana 350 Magnum EMS configuration optimized through spring (either steel spring or gas spring) and rifling twist rate for longer 13 grain and 16 grain .177 pellets.
This, in addition, to other 350 Magnum EMS configurations including .177 slug barrel which would of course have a faster twist rate and no choke.
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Why bother????? ::) ???
-Y
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Why bother????? ::) ???
-Y
1. EMS adds a lot of good improvements.
2. This barrel (or one like it) should come from the factory for the heavy (e.g. JSB Monster and JSB Beast) .177 pellets:
https://www.lothar-walther.com/gun-barrel-blanks/airgun-barrels/polygon-profile-with-choke/1569/airgun-blank-choked-twist-36.177-air-polygon-od.63-l-23.82-precision-rifle-steel-tube (https://www.lothar-walther.com/gun-barrel-blanks/airgun-barrels/polygon-profile-with-choke/1569/airgun-blank-choked-twist-36.177-air-polygon-od.63-l-23.82-precision-rifle-steel-tube)
(See attachment below for specs)
Then, of course, a factory tuned spring and total piston weight (piston, guide, top hat, spring) to make it shoot more efficiently with heavy pellets and thus soft for it's given power. If necessary, print clearly on barrel to avoid lightweight pellets.
The same can be done for the .177 slug configuration which I suspect would use the same spring and piston weight as the heavy pellet optimized .177. However, the barrel would different by using a faster twist with no choke and groove diameter matched very closely to the diameter of the .177 slug which are typically sized .178".
A factory smoothbore for bird shot, optimized diabolo pellets and "shotgun type" slugs could also be made interesting as well.
For people that like the common weight pellets there is always the standard .177 configuration
(barrel, spring, piston weight) that could be used.
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I think it's likelier that we'll see no new high-quality springers ever again than that we'll see a D350 EMS.
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If they touch the last "classic" break barrel springer left in their line up, I will be sorely disappointed.
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Why bother????? ::) ???
-Y
1. EMS adds a lot of good improvements.
2. This barrel (or one like it) should come from the factory for the heavy (e.g. JSB Monster and JSB Beast) .177 pellets:
https://www.lothar-walther.com/gun-barrel-blanks/airgun-barrels/polygon-profile-with-choke/1569/airgun-blank-choked-twist-36.177-air-polygon-od.63-l-23.82-precision-rifle-steel-tube (https://www.lothar-walther.com/gun-barrel-blanks/airgun-barrels/polygon-profile-with-choke/1569/airgun-blank-choked-twist-36.177-air-polygon-od.63-l-23.82-precision-rifle-steel-tube)
(See attachment below for specs)
Then, of course, a factory tuned spring and total piston weight (piston, guide, top hat, spring) to make it shoot more efficiently with heavy pellets and thus soft for it's given power. If necessary, print clearly on barrel to avoid lightweight pellets.
The same can be done for the .177 slug configuration which I suspect would use the same spring and piston weight as the heavy pellet optimized .177. However, the barrel would different by using a faster twist with no choke and groove diameter matched very closely to the diameter of the .177 slug which are typically sized .178".
A factory smoothbore for bird shot, optimized diabolo pellets and "shotgun type" slugs could also be made interesting as well.
For people that like the common weight pellets there is always the standard .177 configuration
(barrel, spring, piston weight) that could be used.
My PCP buddies say .177 slugs are a joke! Even .22 slugs. They say you need to volume of a .25 to push that heavy thing out.
Everybody knows that the Diana 350 is best in .22, so why go on and on about .177? ::) ???
-Y
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Why bother????? ::) ???
-Y
1. EMS adds a lot of good improvements.
2. This barrel (or one like it) should come from the factory for the heavy (e.g. JSB Monster and JSB Beast) .177 pellets:
https://www.lothar-walther.com/gun-barrel-blanks/airgun-barrels/polygon-profile-with-choke/1569/airgun-blank-choked-twist-36.177-air-polygon-od.63-l-23.82-precision-rifle-steel-tube (https://www.lothar-walther.com/gun-barrel-blanks/airgun-barrels/polygon-profile-with-choke/1569/airgun-blank-choked-twist-36.177-air-polygon-od.63-l-23.82-precision-rifle-steel-tube)
(See attachment below for specs)
Then, of course, a factory tuned spring and total piston weight (piston, guide, top hat, spring) to make it shoot more efficiently with heavy pellets and thus soft for it's given power. If necessary, print clearly on barrel to avoid lightweight pellets.
The same can be done for the .177 slug configuration which I suspect would use the same spring and piston weight as the heavy pellet optimized .177. However, the barrel would different by using a faster twist with no choke and groove diameter matched very closely to the diameter of the .177 slug which are typically sized .178".
A factory smoothbore for bird shot, optimized diabolo pellets and "shotgun type" slugs could also be made interesting as well.
For people that like the common weight pellets there is always the standard .177 configuration
(barrel, spring, piston weight) that could be used.
My PCP buddies say .177 slugs are a joke! Even .22 slugs. They say you need to volume of a .25 to push that heavy thing out.
Everybody knows that the Diana 350 is best in .22, so why go on and on about .177? ::) ???
-Y
You are thinking muzzle energy....but I am thinking downrange energy and accuracy.
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I've been following this thread with interest. There are some good ideas here. AND there is also a misunderstanding of the differences between PCP's and Piston guns (whether Gas or Steel spring'ed).
Let's dive into a few concepts:
Piston guns operate in three "phases": Blowgun, Pop-gun, Diesel.
The Blowgun phase is extremely uniform and accurate and it is used mostly in old Match rifles as well as some "F in Pentagon" setups.
The Pop-gun is where most of us like to operate our piston airguns. It has a good thermodinamic efficiency, and it is capable of some fine MV with the right combination of spring, guides, seals,& pellets
It uses the phase conversion of air at very high temperatures to gain that efficiency.
Now, here comes the differences, first between a break barrel rifle and a sliding compression chamber rifle. The main difference is the transfer port length. AND this difference is all important because it means that to reach peak efficiency, the two types of airguns need to be tuned differently.
The break barrels need a long, steady push, with as much pre-load as possible, and any measure that reduces the 1st piston bounce is hugely beneficial.
The sliding compression chamber rifles need a swift compression, a light piston and are not bothered too much by piston bounce.
The DIANA 460 was born just 18 months after the 350. In most markets they entered almost simultaneously. The 460, though, has proven to be a better rifle.
And let's be objective: neither lengths, nor weights differ that much between them.
The underlever takes some getting used to? yes but not that much. You are still pulling the cocking element with your non-trigger hand as you do with your breakbarrel.
So, from the physical/ergonomics POV, they are pretty similar.
The 350 however, does present limitations in the output.
The aim of the EMS is to satisfy the BULK of the production/sales. The 48-56 family will remain a somewhat "specialty" line. The 460 is the "Marilyn Monroe" (slender, svelte, packs a wallop, and is "peculiar" in her tastes), BUT the 350 is just another big breakbarrel of which there are many more in other brands.
IMHO, the 34 EMS still needs time to mature and continue evolving (availability of parts is foremost, then alternate parts, and then different stocks/versions). AGAIN, on a purely personal POV: at least 4-5 more years. After that, we'll see if the concept is better migrated to the 48-54 and 460 families or scaled up to the 350.
Depending on how the market changes in the near future, this idea of mine may change also.
Now, to slugs:
Their natural place is a PCP.
For piston guns, the Diabolo shaped pellet has simply too many advantages.
Specialty slugs could be developed, but then they would not fit as well into the PCP world.
Last aspect is that the 350 NTec was almost a complete failure. There would be no reason to repeat that with a 350 EMS, so, it would be limited to steel springs.
HTH, keep well and shoot straight!
HM
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Huh? I thought the D460 was launched in 2007, or some seven years after the 350 Mag. Plenty of New Gun Buzz from the latter time online, for the underlever magnum.
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Now, to slugs:
Their natural place is a PCP.
For piston guns, the Diabolo shaped pellet has simply too many advantages.
Specialty slugs could be developed, but then they would not fit as well into the PCP world.
While I agree the Diabolo Shape has many advantages, the flare stabilization happens by far the best on the long pellets. In fact, Tom Gaylord did a test (linked below) one decade ago with average weight pellets (which benefit less from flare stabilization than long pellets) and they did better with a 1 in 16" twist than a 1 in 22" twist.
https://www.thefreelibrary.com/A+new+spin+on+air+rifle+twist+rates%3A+most+all+airguns+use+a+twist...-a0344213054 (https://www.thefreelibrary.com/A+new+spin+on+air+rifle+twist+rates%3A+most+all+airguns+use+a+twist...-a0344213054)
Moving on to slugs JSB makes a 10.03 grain .177 slug:
https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html (https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html)
This is light enough to use even in a non magnum gun like the Diana 34 EMS.....so I don't see why 10 grain and heavier .177 slugs should be excluded from more powerful springers. The biggest problem I see with combining slugs and springers is how Lothar Walther sizes their .177 and .217 airgun barrels. For slugs the barrel ideally should be sized .0005" tight (In other words the slug should be sized .0005" over groove diameter). However, Lothar Walther sizes their conventional .177 barrels with a .182" groove diameter. When matched with a .177 slug sized .178 that is going to result in the slug fitting .004" too loose. The Polygonal Lothar Walther .177 barrel is better at .181" groove diameter but it would still be .003" loose when paired with a .177 slug sized .178 (rather than the ideal of .0005" too tight).
Other barrel makers don't oversize their Airgun barrels like Lothar Walther does.
So the problem I see combining springers and slugs is one of making sure the barrel is sized right. That and making sure it has no choke.
No Specialty slugs required.
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While I agree the Diabolo Shape has many advantages, the flare stabilization happens by far the best on the long pellets. In fact, Tom Gaylord did a test (linked below) one decade ago with average weight pellets (which benefit less from flare stabilization than long pellets) and they did better with a 1 in 16" twist than a 1 in 22" twist.
https://www.thefreelibrary.com/A+new+spin+on+air+rifle+twist+rates%3A+most+all+airguns+use+a+twist...-a0344213054 (https://www.thefreelibrary.com/A+new+spin+on+air+rifle+twist+rates%3A+most+all+airguns+use+a+twist...-a0344213054)
Moving on to slugs JSB makes a 10.03 grain .177 slug:
https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html (https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html)
This is light enough to use even in a non magnum gun like the Diana 34 EMS.....so I don't see why 10 grain and heavier .177 slugs should be excluded from more powerful springers. The biggest problem I see with combining slugs and springers is how Lothar Walther sizes their .177 and .217 airgun barrels. For slugs the barrel ideally should be sized .0005" tight (In other words the slug should be sized .0005" over groove diameter). However, Lothar Walther sizes their conventional .177 barrels with a .182" groove diameter. When matched with a .177 slug sized .178 that is going to result in the slug fitting .004" too loose. The Polygonal Lothar Walther .177 barrel is better at .181" groove diameter but it would still be .003" loose when paired with a .177 slug sized .178 (rather than the ideal of .0005" too tight).
Other barrel makers don't oversize their Airgun barrels like Lothar Walther does.
So the problem I see combining springers and slugs is one of making sure the barrel is sized right. That and making sure it has no choke.
No Specialty slugs required.
I don't think you fully understand how a pellet fits into a rifling.
Tom's tests were about rifling TWIST, he did NOT compare different pellet lengths, just rifling twists.
Given the wide array of available pellets, to do an extensive test would be a community effort (which has been done, BTW, in the UK).
Under Tom's tests, the best twist was the standard twist used by almost all makers (1 in 16")
L-W has produced more championship titles than any other barrel maker. I have had the pleasure to work with Frank, personally, on a few projects, one of them even contained non-rifled barrels (smoothbore), LOL!.
I have also had L-W make custom barrels for custom guns, we have explored the twist, the dimensions, and the tolerances, so we know a bit about what we are talking.
I don't think I am revealing any trade secrets when I tell you that the barrels for pellets are made with the specific intention of having the head ride the lands, while the skirt seals the grooves.
THAT defines the internal dimensions of barrels. And that defines what you term "loose" barrels.
Additionally, you seem to forget that the pellet that exits the barrel is FAR from being the pellet that entered the chamber. No problem because everyone forgets that, even Tom Gaylord.
Soft capture a few pellets shot from a magnum and from a match gun, and you will see how the SAME pellet can end up being completely different. Skirts get blown out, waists thicken, heads expand a little.
Slugs, unless specially designed, CANNOT do all this.
Slugs CAN be designed as "dual diameter" slugs and with deep, hollow bases that will act as the skirt of the pellet in the sealing phase, but will not have the drag of the waist.
AFAIK, the JSB KO 0.177" is "coming soon" and therefore, for the time being, made of "unobtainium". I have contacted Predator, and will see exactly what they are when they get here.
BTW, I also have a long standing good relationship with JSB, I have used extensively their pellets and know the brand from the days when Jozef Schültz was still the boss.
It took H&N more than a decade to catch up with some of the concepts embodied in JSB pellets. So, yes I like the JSB guys. AaMoF, we're talking with them about a non-lead alternative in 0.20" cal.
I also have good relations with H&N, but they are a more conservative company and slower to take up new ideas.
It took them 3 years to get the "Baracuda 8" which is not really a Baracuda in the sense that it is a domed, not a streamlined pellet.
And the other great pellet manufacturer is QYS. Their streamlined in 0.177"/ 8.49/4.50 is a great pellet, and the slightly heavier 9.56/4.50 domed is my present choice for FT.
So, . . . . you have four large companies, doing business for over 100 years, some of them, making one style of projectile, and almost ALL the barrel makers "adjusting" to that tradition. And designing barrels that will be accurate AND efficient with that design.
Enter the slugs.
Even PCP's are less efficient with slugs than with pellets. Tested. Not an opinion.
FX started with a 200 years old idea (the "Paradox" rifling) and then decided to change it and their current barrels made for slugs use more traditional ideas.
AND the pressure spike produced by a spring-piston airguns differs completely from the pressure wave produced by a PCP.
The short duration of the piston-driven guns make it VERY hard to drive a projectile with a much larger friction than a pellet to usable MV's
Even a Hatsan 135, slows down CONSIDERABLY with slugs in the 8-9.5 grains region (again, tested, not an opinion). And these guns have huge swept volumes.
Getting ALL those different groups and interests together is going to take some time.
If slugs are ever going to be useful in piston guns, you NEED a special slug.
If you have the time read these:
https://www.ctcustomairguns.com/hectors-airgun-blog/at-the-moment-of-firing-and-fit-of-pellet-to-the-rifling (https://www.ctcustomairguns.com/hectors-airgun-blog/at-the-moment-of-firing-and-fit-of-pellet-to-the-rifling)
https://www.ctcustomairguns.com/hectors-airgun-blog/the-universal-pellet-is-here (https://www.ctcustomairguns.com/hectors-airgun-blog/the-universal-pellet-is-here)
https://www.ctcustomairguns.com/hectors-airgun-blog/the-durango-kid-is-coming-to-town (https://www.ctcustomairguns.com/hectors-airgun-blog/the-durango-kid-is-coming-to-town)
Apologies for the long post.
Keep well and shoot straight!
HM
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While I agree the Diabolo Shape has many advantages, the flare stabilization happens by far the best on the long pellets. In fact, Tom Gaylord did a test (linked below) one decade ago with average weight pellets (which benefit less from flare stabilization than long pellets) and they did better with a 1 in 16" twist than a 1 in 22" twist.
https://www.thefreelibrary.com/A+new+spin+on+air+rifle+twist+rates%3A+most+all+airguns+use+a+twist...-a0344213054 (https://www.thefreelibrary.com/A+new+spin+on+air+rifle+twist+rates%3A+most+all+airguns+use+a+twist...-a0344213054)
Moving on to slugs JSB makes a 10.03 grain .177 slug:
https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html (https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html)
This is light enough to use even in a non magnum gun like the Diana 34 EMS.....so I don't see why 10 grain and heavier .177 slugs should be excluded from more powerful springers. The biggest problem I see with combining slugs and springers is how Lothar Walther sizes their .177 and .217 airgun barrels. For slugs the barrel ideally should be sized .0005" tight (In other words the slug should be sized .0005" over groove diameter). However, Lothar Walther sizes their conventional .177 barrels with a .182" groove diameter. When matched with a .177 slug sized .178 that is going to result in the slug fitting .004" too loose. The Polygonal Lothar Walther .177 barrel is better at .181" groove diameter but it would still be .003" loose when paired with a .177 slug sized .178 (rather than the ideal of .0005" too tight).
Other barrel makers don't oversize their Airgun barrels like Lothar Walther does.
So the problem I see combining springers and slugs is one of making sure the barrel is sized right. That and making sure it has no choke.
No Specialty slugs required.
I don't think you fully understand how a pellet fits into a rifling.
Tom's tests were about rifling TWIST, he did NOT compare different pellet lengths, just rifling twists.
Given the wide array of available pellets, to do an extensive test would be a community effort (which has been done, BTW, in the UK).
Under Tom's tests, the best twist was the standard twist used by almost all makers (1 in 16")
L-W has produced more championship titles than any other barrel maker. I have had the pleasure to work with Frank, personally, on a few projects, one of them even contained non-rifled barrels (smoothbore), LOL!.
I have also had L-W make custom barrels for custom guns, we have explored the twist, the dimensions, and the tolerances, so we know a bit about what we are talking.
I don't think I am revealing any trade secrets when I tell you that the barrels for pellets are made with the specific intention of having the head ride the lands, while the skirt seals the grooves.
THAT defines the internal dimensions of barrels. And that defines what you term "loose" barrels.
(Snip)
AFAIK, the JSB KO 0.177" is "coming soon" and therefore, for the time being, made of "unobtainium". I have contacted Predator, and will see exactly what they are when they get here.
1. Tom Gaylord tested only regular weight pellets which are short. These are the type of pellets have a flare which sees less of the air flow than the heavy ones which are longer. This is why they need to have faster twist.
2. I've always known the JSB and other pellets are designed as a bore riding design with the head diameter smaller than the skirt diameter. This to reduce friction and to help the flare see more of the air flow.
See below picture of one of rsterne's .217 pellet designs to see how head is smaller than skirt.
Okay, so with that our of the way what obviously makes a good pellet barrel does not make for a good slug barrel. This is why EMS should have a dedicated slug barrel in addition to the pellet barrels.
P.S. The JSB .177 10.03 grain knockout slugs have been around for a while and even tested in springer guns. The results have been promising.
Yes, it is possible, to make slugs with less friction by using a reduced diameter center section (see Bob's Boat tails aka BBTs) but the bearing surface on the JSB .177 10.03 grain slugs is pretty short so this shouldn't be a issue. Main thing is to get the slug fitting close to the groove diameter so it travels down the barrel straight.
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Here is a review I found of a HW95 (which I saw listed as having a spec of 11.6 FPE in .177) getting an average of 9.6 FPE when using the .177 JSB 10.03 grain slugs. This is pretty good considering the gun is most likely very optimized for light pellets (because of piston weight, spring, etc.) and the loose fit of slug in barrel is resulting in the spike of high pressure air blowing past the slug in the barrel resulting in power loss.
https://youtu.be/klEsDeRJVGI
Now just imagine what could happen with a purpose built slug barrel (e.g. tighter fit of slug to barrel, shorter lands like a .172 powder burner for less friction, no choke, etc.)
Heck, even if the optimized slug barrel made a bit less power at the muzzle than an equivalent weight pellet in a LW pellet barrel....ask yourself how much more energy does it have on the target. Remember it's the energy on target that actually matters.
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You want energy on target use a larger caliber. Reliable hunters who hunt with .177 do with shot placement not energy on target. Maybe you should practice precision shooting. !/2 inch groups of less. Anyway, since springers are a dying breed, all you ideas are just "pie in the sky". ;D ;D ;D ;D ;D
-Y
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You want energy on target use a larger caliber. Reliable hunters who hunt with .177 do with shot placement not energy on target. Maybe you should practice precision shooting. !/2 inch groups of less. Anyway, since springers are a dying breed, all you ideas are just "pie in the sky". ;D ;D ;D ;D ;D
-Y
A .22 pellet won't put more energy on target than a .177 slug unless the range is very close. I'm confident it will also be less accurate than a long and heavy .177 pellet using a very slow twist .177 pellet barrel like the Lothar Walther 1 in 36" twist polygon .177 airgun barrel I linked in post #3 of this thread---> https://www.gatewaytoairguns.org/GTA/index.php?topic=206544.0#msg156425098 (https://www.gatewaytoairguns.org/GTA/index.php?topic=206544.0#msg156425098)
So if your goal is very short range the classic .22 pellet configuration still works. Different horses for different courses.
P.S. Everything I have written about .177 can be applied to the .20 and .22 as well. (The .20, however, at this time suffers from a lack of long heavy pellets and the slow twist Lothar Walther pellet barrel that ideally go along with the long heavy pellets. There are also a lack of .20 slugs last time I checked as well. Hopefully this changes.)
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Well Under Pressure,
Why don't you make the gun you want? Get your Lothar Walther barrel, modify the gun's action, get a stock maker to make you a bull pup stock. DO IT and report back.....
Or better yet, get 500 people to sign up for one, get them to pay in advance, then go to Germany with the cash in hand and ask them to make it. Money talks, BS walks... ;)
-Y
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Or better yet, get 500 people to sign up for one, get them to pay in advance, then go to Germany with the cash in hand and ask them to make it. Money talks, BS walks... ;)
-Y
JSB Knockout slugs are now about the same price as JSB pellets of the same weight. People want to slugs....and now price is no longer an obstacle. The slug barrels will come no doubt about that.
In fact, transitioning to slug barrels was no doubt part of the reason EMS was developed.
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Why bother????? ::) ???
-Y
+1
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Or better yet, get 500 people to sign up for one, get them to pay in advance, then go to Germany with the cash in hand and ask them to make it. Money talks, BS walks... ;)
-Y
JSB Knockout slugs are now about the same price as JSB pellets of the same weight. People want to slugs....and now price is no longer an obstacle. The slug barrels will come no doubt about that.
In fact, transitioning to slug barrels was no doubt part of the reason EMS was developed.
Same price for 350 vs 500 in a pellet tin. Build what you want and then report back. C'uss what you want ain't going to happen otherwise. :-[
-Y
PS all the sub-MOA shooters, at 200 yards at the range say that you need minimum of 925+fps to stabilise slugs. Yes, they are shooting .25 cal FX guns.
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Or better yet, get 500 people to sign up for one, get them to pay in advance, then go to Germany with the cash in hand and ask them to make it. Money talks, BS walks... ;)
-Y
JSB Knockout slugs are now about the same price as JSB pellets of the same weight. People want to slugs....and now price is no longer an obstacle. The slug barrels will come no doubt about that.
In fact, transitioning to slug barrels was no doubt part of the reason EMS was developed.
Same price for 350 vs 500 in a pellet tin.
PS all the sub-MOA shooters, at 200 yards at the range say that you need minimum of 925+fps to stabilise slugs. Yes, they are shooting .25 cal FX guns.
The knockout slugs come 500 in a tin, not 350:
https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html (https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html) ($23.99 for 500 .177 JSB Knockout 10.03 grain slugs)
https://www.airgundepot.com/jsb-546267.html (https://www.airgundepot.com/jsb-546267.html) ($22.99 for 500 .177 JSB exact heavy 10.3 grain diabolo pellets)
As you can see JSB slugs are now about the same price as JSB pellets.
Edit: When comparing 13.4 grain .177 JSB slugs to 13.4 grain .177 JSB pellets I see the slugs are a few bucks cheaper:
https://www.airgundepot.com/jsb-knockout-slugs-177-cal-13.43-gr-400-ct.html (https://www.airgundepot.com/jsb-knockout-slugs-177-cal-13.43-gr-400-ct.html) ($19.99 for 400 .177 JSB 13.4 grain slugs)
https://www.airgundepot.com/jsb-exact-monster-diabolo-177-caliber-13-4-grain-400-count.html (https://www.airgundepot.com/jsb-exact-monster-diabolo-177-caliber-13-4-grain-400-count.html) ($22.99 for 400 .177 JSB 13.4 grain pellets)
P.S. The reason why long range shooters use 925+ fps is because that speed is best for wind drift, it has nothing to do with stabilization of the bullet. As far as rifling twist requirements go its just the opposite of what you think....the slower the velocity below supersonic the less rifling twist required (for any given atmospheric pressure and temperature). See Kolbe Twist calculator below for examples:
http://www.geoffrey-kolbe.com/barrel_twist.htm (http://www.geoffrey-kolbe.com/barrel_twist.htm)
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Back to the original EMS 350 question, what made the Ntec 350 have such a high cocking weight? My 340 seems a bit stiffer than my 34's but not too much. Was it the ram, mechanical design or a combination of both?
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Or better yet, get 500 people to sign up for one, get them to pay in advance, then go to Germany with the cash in hand and ask them to make it. Money talks, BS walks... ;)
-Y
JSB Knockout slugs are now about the same price as JSB pellets of the same weight. People want to slugs....and now price is no longer an obstacle. The slug barrels will come no doubt about that.
In fact, transitioning to slug barrels was no doubt part of the reason EMS was developed.
Same price for 350 vs 500 in a pellet tin.
PS all the sub-MOA shooters, at 200 yards at the range say that you need minimum of 925+fps to stabilise slugs. Yes, they are shooting .25 cal FX guns.
The knockout slugs come 500 in a tin, not 350:
https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html (https://www.airgundepot.com/jsb-knockout-slugs-177-cal-10.03-gr-500-ct.html) ($23.99 for 500 .177 JSB Knockout 10.03 grain slugs)
https://www.airgundepot.com/jsb-546267.html (https://www.airgundepot.com/jsb-546267.html) ($22.99 for 500 .177 JSB exact heavy 10.3 grain diabolo pellets)
As you can see JSB slugs are now about the same price as JSB pellets.
Edit: When comparing 13.4 grain .177 JSB slugs to 13.4 grain .177 JSB pellets I see the slugs are a few bucks cheaper:
https://www.airgundepot.com/jsb-knockout-slugs-177-cal-13.43-gr-400-ct.html (https://www.airgundepot.com/jsb-knockout-slugs-177-cal-13.43-gr-400-ct.html) ($19.99 for 400 .177 JSB 13.4 grain slugs)
https://www.airgundepot.com/jsb-exact-monster-diabolo-177-caliber-13-4-grain-400-count.html (https://www.airgundepot.com/jsb-exact-monster-diabolo-177-caliber-13-4-grain-400-count.html) ($22.99 for 400 .177 JSB 13.4 grain pellets)
P.S. The reason why long range shooters use 925+ fps is because that speed is best for wind drift, it has nothing to do with stabilization of the bullet. As far as rifling twist requirements go its just the opposite of what you think....the slower the velocity below supersonic the less rifling twist required (for any given atmospheric pressure and temperature). See Kolbe Twist calculator below for examples:
http://www.geoffrey-kolbe.com/barrel_twist.htm (http://www.geoffrey-kolbe.com/barrel_twist.htm)
After looking for, and not finding any on dealers (PA, AoA, AD, etc.) websites, Predator Int'l very kindly offered to send three tins for testing.
They will arrive on Monday.
I will keep you posted.
HM
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Back to the original EMS 350 question, what made the Ntec 350 have such a high cocking weight? My 340 seems a bit stiffer than my 34's but not too much. Was it the ram, mechanical design or a combination of both?
Simple mechanics.
In a 34/340 scenario, the arc of the cocking lever is not pronounced enough to distance the fulcrum point from the axis of movement.
When you add an inch to the length of the stroke, then the fulcrum point moves out, and the pressure rise inside the ram is rather flat, so when you have ALREADY compressed some, the challenge gets harder because you are being "cheated" by the moving of the fulcrum out of the axis.
In the 34 EMS, this is corrected with a shorter secondary length in the cocking linkage and an increased arc for cocking.
If a 350 were to be built with the same architecture, then the same problem would occur.
Now, it is not as bad to go from 35# to 40# as it was to go from 40# to #45. The body feels the situations completely different, even if the overage is the same.
Hope I made sense.
Keep well and shoot straight!
HM
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Thanks, Hector.