This is best video on basic tuning I've found, I followed it and went from there to get what I wanted, the rest is a matter of preference.My Armada is tuned with H&N 18s to about 900fps with a standard deviation of around, I get 30 shots plus before any significant drop off, never saw the need for a regulator, it shoots accurately enough and consistently enough without one.
The standard Mrod was commonly tuned to 30 shots @ 30FPE (4% Es). 30FPE is plenty for your occasional wood chuck. Not sure if it can be tuned down to 10FPE without mods. At 10FPE the pellet arc would be significant for 50 yd shooting. I'd recommend picking something between 20-30FPE. For that occasional wood chuck, I'd keep it toward the 30FPE end. 30FPE is certainly way more than needed for the chipmunk though. Regardless of power, accuracy is king. To estimate the shot count of a lower than 30FPE tune, calculate based on total FPE. Total FPE = 30FPE X 30 shots = 900FPE. Divide the Total FPE by the lower power you'd like, say 25FPE. 900/25 = 36 Shots. In practice, when going to a lower power, you gain a shot or two more than calculated. Going higher, usually can't quite achieve the calculated. Conventional tuning along with finding the most accurate pellet at the power you want is time consuming. Expect to spend allot of time with the chrony. If it gets frustrating, shoot some cans and put it down for a while. Pick it back up on another day.
The gun was designed for 3K fills and shoot down to 2K or a little lower. That 900fpe total is based on that pressure range. 2K to 1K will have significantly less and hammer will be too heavy, and will need other mods to operate well in that pressure range.
Quote from: FuzzyGrub on October 13, 2021, 07:19:37 PMThe gun was designed for 3K fills and shoot down to 2K or a little lower. That 900fpe total is based on that pressure range. 2K to 1K will have significantly less and hammer will be too heavy, and will need other mods to operate well in that pressure range.Agreed. Factory hammer works well between 2800-1800 psi, give or take.Record all factory settings before tuning.Back off hammer spring tension all the way. Then play with velocity screw to get desired fps with prefered pellets. Shoot from 2800psi to 1800psi (or 2000, what ever you want to pump from) and record numbers. You may need to adjust hammer spring tension to level out velocity spread. Higher tension if mid or late numbers peak, or lower tension if numbers peak in beginning and just drop. You want the lightest spring tension that gives the tightest velocity spread. Fine tune with hammer travel if you want to get picky.After all done tuning, if you want adjustments in velocity, just use velocity screw. Just leave other settings for efficiency. More power will use more Air and vise-versa. ~20Ftlbs in .22 should be a decent minimum for 50 yard work on woodchucks yet give decent trajectory for squirrel or chipmunks. Depending on the pellets.Greatly increasing Hammer spring setting won't make too big of a power difference unless you go for BIG power at higher pressure. (Don't exceed manufacturers limit). Usually just wastes air...With my Gen 2 .177 Marauder, I get 80 shots @ near constant 10fpe all factory parts. Softest hammer strike, factory hammer throw. Forgot velocity screw settings, either 1.25 or .75 turns from bottem. Good for chippers and squirrel to 30-35 yards with 7.9gr CPHP's. Can go down to ~6fpe and up to 18+fpe just playing with velocity screw and using same 7.9gr .177 pellets. Never shot with velocity screw open all the way, that I recall.
I have tinkered a bit with my unregulated .22 Synrod. Attached are a few different tunes I have setup on it. I like to tune for number of mags with ES always in mind.You can see the top string tuned to 32 shots (3 mags) averaging 30.74 FPE that is within a 2% extreme spread (ES) using JSB 18.13gr. The middle tuned for 4 mags averaging 29 FPE within a 3% ES with same JSBs. The last string 6 mags within a 4% ES averaging 29.61 FPE using AA 16gr. All while filling to max psi.I would recommend you leave the porting OEM and open the brass valve screw all the way open. I would also recommend you replace the valve spring with a .25 cal valve spring (lighter spring) and seek out a MDF lightweight hammer and some additional hammer springs in the 12 lb rating. These items made my tunes with a respectable ES more achievable.In OEM stock form it will be harder to achieve lower ES numbers as it is not as well balance between hammer weight, valve spring and fill pressure. You should be good out to 50 yards sticking within a 4% ES tune or less.
Quote from: triggertreat on October 14, 2021, 02:31:27 PMI have tinkered a bit with my unregulated .22 Synrod. Attached are a few different tunes I have setup on it. I like to tune for number of mags with ES always in mind.You can see the top string tuned to 32 shots (3 mags) averaging 30.74 FPE that is within a 2% extreme spread (ES) using JSB 18.13gr. The middle tuned for 4 mags averaging 29 FPE within a 3% ES with same JSBs. The last string 6 mags within a 4% ES averaging 29.61 FPE using AA 16gr. All while filling to max psi.I would recommend you leave the porting OEM and open the brass valve screw all the way open. I would also recommend you replace the valve spring with a .25 cal valve spring (lighter spring) and seek out a MDF lightweight hammer and some additional hammer springs in the 12 lb rating. These items made my tunes with a respectable ES more achievable.In OEM stock form it will be harder to achieve lower ES numbers as it is not as well balance between hammer weight, valve spring and fill pressure. You should be good out to 50 yards sticking within a 4% ES tune or less.I appreciate the advice. My ES is nothing like yours.There are a lot of acronyms. I can't seem to find anything about a Marauder MDF lightweight hammer. I have seen people buying aftermarket parts but some of those vendors appear to be out of business or not making parts anymore. JSAR is an example.Where does one get a .25 valve spring? I went to a site and it appeared that the .22 and .25 are the same spring according to them. I can't find a 12 pound hammer spring either. Where do people shop? I see HillAirGun but JSAR doesn't seem to be too operational at the moment.
Quote from: Underwhere on October 14, 2021, 05:17:29 PMQuote from: triggertreat on October 14, 2021, 02:31:27 PMI have tinkered a bit with my unregulated .22 Synrod. Attached are a few different tunes I have setup on it. I like to tune for number of mags with ES always in mind.You can see the top string tuned to 32 shots (3 mags) averaging 30.74 FPE that is within a 2% extreme spread (ES) using JSB 18.13gr. The middle tuned for 4 mags averaging 29 FPE within a 3% ES with same JSBs. The last string 6 mags within a 4% ES averaging 29.61 FPE using AA 16gr. All while filling to max psi.I would recommend you leave the porting OEM and open the brass valve screw all the way open. I would also recommend you replace the valve spring with a .25 cal valve spring (lighter spring) and seek out a MDF lightweight hammer and some additional hammer springs in the 12 lb rating. These items made my tunes with a respectable ES more achievable.In OEM stock form it will be harder to achieve lower ES numbers as it is not as well balance between hammer weight, valve spring and fill pressure. You should be good out to 50 yards sticking within a 4% ES tune or less.I appreciate the advice. My ES is nothing like yours.There are a lot of acronyms. I can't seem to find anything about a Marauder MDF lightweight hammer. I have seen people buying aftermarket parts but some of those vendors appear to be out of business or not making parts anymore. JSAR is an example.Where does one get a .25 valve spring? I went to a site and it appeared that the .22 and .25 are the same spring according to them. I can't find a 12 pound hammer spring either. Where do people shop? I see HillAirGun but JSAR doesn't seem to be too operational at the moment.The valve spring, Crosman. The MDF hammer, Rocker1, he is a member here. Send him a PM.Also here is a ton of info I have gathered together in the form of a bookmark list.