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FX Bobcat: Air Leaks and Other Issues

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vaughn cordle
vaughn cordle

This new Bobcat .25 owner's experience has not been a good one. Air leaks, lever jams, regulator issues, and scope sighting problems were experienced during the first 1500 pellets. The second Bobcat has been returned to the dealer for replacement or repair. Air leaks in the newly designed Bobcat are the result of a poorly designed "stack" of dowdy seals. The air leak problem has a solution and it requires a manufacturer-designed new unit that replaces the stack of 5 seals currently used. There are also variations in muzzle velocities and POI accuracy issues that must be professionally addressed and corrected. Other issues are presented as I learned the gun and how best to address issues that, in part, may be due to new design problems and what typically happens when breaking in a new gun. It does appear that the new Bobcat has quality control issues that require professional help before it can perform to its accuracy potential.

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Vaughn Cordle, CFA / March 7, 2014 FX Bobcat .25 Air Leak and Other Issues: New User Experience March 15, 2014 update / First 1500 pellets
Summary of experience and problems with the new Bobcat 25 FX has designed an exciting new Bobcat that has proven to be very accurate and popular with experienced air gun operators. This is why I bought the new FX product. However, as I quickly learned, the Bobcat has air leak problems and other issues that must be addressed by the new gun owner and/or distributor. The new stock design required a lengthening of the male fill component for easy access and use. The FX solution was a quick fix that involved stacking too many spacers/seals/washers in a manner that results in air leaks if the fill component is moved or jarred. Normal use of the fill component suggests that this poor design will require repeated adjustments of the seal stack over time to manage air leaks. One fix could be a redesign of the stack and/or the fill component. Those interested in buying the new Bobcat may want to wait until FX provides a proper design solution to the need to lengthen the fill component. The first two Bobcats I received had leaks. The first was replaced and I fixed the second one by aligning the misaligned 5 piece dowdy stack and tightening the fill component. This was an easy fix. Unfortunately, the second Bobcat had lever jamming, regulator, and sighting issues which impacted the ease of use and accuracy. The second Bobcat was also returned to the dealer. While I like the design, without the accuracy there is no reason to own the gun. So, if the dealer will not replace the rifle with a new one, or correct the major issues, I will ask for a refund. Ill update this 際際滷Share presentation once the new or repaired Bobcat has been received and tested.
Air Leak Issue Air leaks may be the result of improperly installed dowdy seals/washers 5 in total - that are stacked to extend the male air fill component used in the new stock design. This extend-the-fill-fix solved one problem but now requires its own fix to eliminate current and future air leaks. The integrity of the stacked washers and welded copper pipe should be a major concern for those thinking about buying the newly designed Bobcat. Any bump or movement in the male fill component could break the seals and result in an air leak. Possible solution: Replace the 5 stacked seals with one unit. The gun owner risks breaking off the welded copper pipe when adjusting misaligned seals to stop air leaks.
The distributors solution replace seals - may fix the stacked seal leak problem, but it creates exactly the same problem the stacked seals were originally designed to fix inadequate length of the male fill component when fitted into the new Bobcat stock. One solution is to design a dowdy seal replacement that is as thick as 4 or 5 normal-sized seals. This will reduce the risks of future air leaks caused by movement of the fill component. The distributors solution is to replace five (5) stacked seals/spacers with only two (2) dowdy seals. The leak- prone stack includes three (3) dowdy seals and two (2) additional spacers/washers.
Lever Jamming /Magazine Issue The firing lever has jammed four times and this has resulted in the firing pin (#1) digging into the pellet magazine (#2) and difficulty in removing the magazine after the last pellet is shot. Jiggling the magazine in an attempt to remove has scraped off the edge of the slot (#3) that slides into the gun. Small particles of metal from pellet clipping and/or from the magazine jiggling likely impeded the hammer stroke which in turn caused major drops in pellet velocity and accuracy problems. Occasionally the magazine would not advance properly, and this in turn resulted in misfires or double pellet loading and pellet clipping. Possible solution: Replace magazine and/or adjust the delrin? guide set screw. 2 1 3
Regulator Issue Large variations in velocity impact accuracy. Four chrony strings were produced and compared to five other Bobcat owners results. Teds string and 2 ft/s standard deviation represents an optimal consistency in velocity. My test produced a high standard deviation of 8 ft/s when big drops in pressure are excluded. Possible solution: Replace the regulator. String #3: includes big drops in velocity, likely due to pellet clipping and/or particles from jiggling the magazine when the lever jammed. String #4 is very inconsistent with a standard deviation (8 ft/s) that is 4X higher than Teds when bad shots are excluded.
Scope Sighting Issue The second Bobcat I received requires the scope windage and elevation adjustments to be at the extreme limits to match the crosshair with the POI. Even at 30 yards the scope runs out of UP movement and is near or at the limits of the UP and RIGHT settings at 80 yards. This may be a major problem if the barrel is out of alignment. And, it is a very irritating problem when trying to sight the scope. Possible solutions: Adjustable scope mounts or adjust the rifle railing where the scope mounts attach. If it is a barrel alignment problem, replace the rifle.
Accuracy Issues I Consistency in velocity impacts accuracy and a high standard deviation (SD) in velocity (ft/s) will result in a wider variation in the target point of impact (POI) than a low SD, especially over the longer ranges. Example: For a 75 yard shot (scope zeroed at 50 yards and median of 888 ft/s) a low- high spread of 20 ft/s will have a POI (height) variation of .29 of an inch, and at 100 feet it will be .86 inch . A spread of only 4 ft/s has a POI variation of only .05 inches at 75 and .16 at 100 feet. This difference in accuracy is significant if the target is the head of a small pest or if the rifle is used for bench rest competition. For this reason, the Bobcat regulator must produce a consistent velocity if the rifle is to perform to its accuracy potential. Given the crony results of 6 different [regulated] Bobcat 25 owners, it appears that there are large [velocity SD] variances in regulator performance in the first batch of new Bobcats. A SD of 2 ft/s is optimal and SDs greater than say 5 ft/s should be addressed and corrected by adjusting [or replacing] the regulator or hammer spring/preload?.
Accuracy Issues II A median velocity of 920 (ft/s) provides tighter groupings and less turns (clicks) for scope sighting at 75 and 100 yards than the lower 888 ft/s. And, a smaller low-high spread in velocity improves variation in POI [height] accuracy. The Zero Range is set to 50 yards
Accuracy Issues III Regulated Bobcat #1 (vaughns) has a larger variation in velocity and POI accuracy than. Bobcat #2 (Teds) that is clearly more accurate at 75 and 100 yards.

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FX Bobcat: Air Leaks and Other Issues

  • 1. Vaughn Cordle, CFA / March 7, 2014 FX Bobcat .25 Air Leak and Other Issues: New User Experience March 15, 2014 update / First 1500 pellets
  • 2. Summary of experience and problems with the new Bobcat 25 FX has designed an exciting new Bobcat that has proven to be very accurate and popular with experienced air gun operators. This is why I bought the new FX product. However, as I quickly learned, the Bobcat has air leak problems and other issues that must be addressed by the new gun owner and/or distributor. The new stock design required a lengthening of the male fill component for easy access and use. The FX solution was a quick fix that involved stacking too many spacers/seals/washers in a manner that results in air leaks if the fill component is moved or jarred. Normal use of the fill component suggests that this poor design will require repeated adjustments of the seal stack over time to manage air leaks. One fix could be a redesign of the stack and/or the fill component. Those interested in buying the new Bobcat may want to wait until FX provides a proper design solution to the need to lengthen the fill component. The first two Bobcats I received had leaks. The first was replaced and I fixed the second one by aligning the misaligned 5 piece dowdy stack and tightening the fill component. This was an easy fix. Unfortunately, the second Bobcat had lever jamming, regulator, and sighting issues which impacted the ease of use and accuracy. The second Bobcat was also returned to the dealer. While I like the design, without the accuracy there is no reason to own the gun. So, if the dealer will not replace the rifle with a new one, or correct the major issues, I will ask for a refund. Ill update this 際際滷Share presentation once the new or repaired Bobcat has been received and tested.
  • 3. Air Leak Issue Air leaks may be the result of improperly installed dowdy seals/washers 5 in total - that are stacked to extend the male air fill component used in the new stock design. This extend-the-fill-fix solved one problem but now requires its own fix to eliminate current and future air leaks. The integrity of the stacked washers and welded copper pipe should be a major concern for those thinking about buying the newly designed Bobcat. Any bump or movement in the male fill component could break the seals and result in an air leak. Possible solution: Replace the 5 stacked seals with one unit. The gun owner risks breaking off the welded copper pipe when adjusting misaligned seals to stop air leaks.
  • 4. The distributors solution replace seals - may fix the stacked seal leak problem, but it creates exactly the same problem the stacked seals were originally designed to fix inadequate length of the male fill component when fitted into the new Bobcat stock. One solution is to design a dowdy seal replacement that is as thick as 4 or 5 normal-sized seals. This will reduce the risks of future air leaks caused by movement of the fill component. The distributors solution is to replace five (5) stacked seals/spacers with only two (2) dowdy seals. The leak- prone stack includes three (3) dowdy seals and two (2) additional spacers/washers.
  • 5. Lever Jamming /Magazine Issue The firing lever has jammed four times and this has resulted in the firing pin (#1) digging into the pellet magazine (#2) and difficulty in removing the magazine after the last pellet is shot. Jiggling the magazine in an attempt to remove has scraped off the edge of the slot (#3) that slides into the gun. Small particles of metal from pellet clipping and/or from the magazine jiggling likely impeded the hammer stroke which in turn caused major drops in pellet velocity and accuracy problems. Occasionally the magazine would not advance properly, and this in turn resulted in misfires or double pellet loading and pellet clipping. Possible solution: Replace magazine and/or adjust the delrin? guide set screw. 2 1 3
  • 6. Regulator Issue Large variations in velocity impact accuracy. Four chrony strings were produced and compared to five other Bobcat owners results. Teds string and 2 ft/s standard deviation represents an optimal consistency in velocity. My test produced a high standard deviation of 8 ft/s when big drops in pressure are excluded. Possible solution: Replace the regulator. String #3: includes big drops in velocity, likely due to pellet clipping and/or particles from jiggling the magazine when the lever jammed. String #4 is very inconsistent with a standard deviation (8 ft/s) that is 4X higher than Teds when bad shots are excluded.
  • 7. Scope Sighting Issue The second Bobcat I received requires the scope windage and elevation adjustments to be at the extreme limits to match the crosshair with the POI. Even at 30 yards the scope runs out of UP movement and is near or at the limits of the UP and RIGHT settings at 80 yards. This may be a major problem if the barrel is out of alignment. And, it is a very irritating problem when trying to sight the scope. Possible solutions: Adjustable scope mounts or adjust the rifle railing where the scope mounts attach. If it is a barrel alignment problem, replace the rifle.
  • 8. Accuracy Issues I Consistency in velocity impacts accuracy and a high standard deviation (SD) in velocity (ft/s) will result in a wider variation in the target point of impact (POI) than a low SD, especially over the longer ranges. Example: For a 75 yard shot (scope zeroed at 50 yards and median of 888 ft/s) a low- high spread of 20 ft/s will have a POI (height) variation of .29 of an inch, and at 100 feet it will be .86 inch . A spread of only 4 ft/s has a POI variation of only .05 inches at 75 and .16 at 100 feet. This difference in accuracy is significant if the target is the head of a small pest or if the rifle is used for bench rest competition. For this reason, the Bobcat regulator must produce a consistent velocity if the rifle is to perform to its accuracy potential. Given the crony results of 6 different [regulated] Bobcat 25 owners, it appears that there are large [velocity SD] variances in regulator performance in the first batch of new Bobcats. A SD of 2 ft/s is optimal and SDs greater than say 5 ft/s should be addressed and corrected by adjusting [or replacing] the regulator or hammer spring/preload?.
  • 9. Accuracy Issues II A median velocity of 920 (ft/s) provides tighter groupings and less turns (clicks) for scope sighting at 75 and 100 yards than the lower 888 ft/s. And, a smaller low-high spread in velocity improves variation in POI [height] accuracy. The Zero Range is set to 50 yards
  • 10. Accuracy Issues III Regulated Bobcat #1 (vaughns) has a larger variation in velocity and POI accuracy than. Bobcat #2 (Teds) that is clearly more accurate at 75 and 100 yards.