narach93 wrote:Thanks Basuda, Nitroex700 and Prashantji for your valuable advice. The fact is that I have a .22 SX 100 as well as a .177 NX 100. My query was only academic. I have also posted a mail to the precohole to seek their opinion. However I will try to swap the barrel and check the performance by my chrono. Infact the technical description bug of Prasantji has bitten me and I have done some experiments and learn some hard facts. Very soon I will share my part of story.
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Dear vsraja. Are you sure that Precihole is developing Sx/nx 200 ? If it is true then it will turn around the air rifle scenario of our country. Taking into account of their quality, the 200 will be a fantastic product. I guess they will settle for 20 joule which will allow many budding shooters to practice for 50 meters. Precihole should try to tap those customers who always wants for foreign ARs but cannot afford one. This is indeed a welcome information.
Dear Narach93,
So glad to hear you are onto some experimenting! Will be looking forward to hearing further on it please.
Credible and authoritative sources have confirmed that a more powerful PH springer is in the offing....sooner rather than later; most certainly with a longer stroke. Some even say that we could look forward to it sometime around this Diwali season! What a terrific Diwali gift it would be!!
What stroke length it would be...continues to be a guess work for us as of now. However, since you say that the technical bug has bitten you, let me share some details on this from my on-going LONG-STROKING experiments with my PH springer.
[I no more feel inclined to share the tech details publicly because mostly people are least inclined.]
I have extended the stroke on my VX from 77 to 85+mm...and have so far run and tested it in three different states of tune.
First things first: In the existing action, and with a similar spring energy, this gun in 85mm stroke is the softest of any springers you would have ever shot, I guarantee......and with an instant ME figure in the range of 9.5FPE to 11FPE across the different weight pellets FLAT OUT straight upon assembly. The shot cycles are so soft and stable, you could shoot one holers at short ranges with one hand. First test shots produced a 1/4" to 1/3" POI at 7mtrs with six different pellets. And lo and behold,.....all this with a cocking effort of BELOW 8KG...i.e. 17 pounds!!
Energy Efficiency is in 32% range ...but that is because a large portion of spring energy gets invested with the piston (83.5%) and much less with preload.
A slight alteration of the spring and PL energy takes it swiftly into the 10.5-13fpe zone...with same accuracy, swifter shot cycle feel and lower sensitivity, and cocking effort just below 9KG. EE shoots up to over 35% with the lightest pellet....and over 33% with both -the most accurate one (PH-8.2) and the heavier yet loose fit one (US-Super Pointed, 9.6). The proportion of piston energy here is slightly lower at 81.22% of the spring energy.
Tweak it further, and it becomes tricky...in that accuracy becomes laboured (read the gun starts becoming sensitive, cycle is perceptibly snappy, esp with lighter pellets).
However, a lot of it, as I am figuring out through the different states of tune, is really about getting the piston weight, the spring room and the spring and preload energy right....and I am continuing to work out that sweet spot through the various tunes I am trying currently.
Now, coming to Precihole Sports: My view is that if they settle with 85-86mm stroke, we can expect the final product pretty soon...as they would not need to alter the comp tube, and could manage a sweet shooting, low effort, yet inherently higher powered gun with very few changes (makes good commercial sense!). It can be made to shoot at higher ME ...but the cycle could get pretty snappy (may get even harsher) and with heavier cocking. Would you like one? I may not.
However, if they decide on giving us a sweet-shooter 20J gun (I repeat, a sweet-shooter!), then I guess, they will need to alter the action (most certainly, the cocking link slot)....and so, we might need to wait a while longer (to allow for additional alterations in the production line, new moulds for action, etc.).
Going by the taste and commitment of Precihole's chief designer, Dr. Shirsat, we certainly should expect a sweet shooter powerhouse (as against jerky bone wrecker magnums that there are so many!!)
Just some top-of-mind thoughts... So much for now.
Best regards,
Prashant