There are a few things that could cause that...Just to name a couple..Misaligned valve to tp to barrel.Damaged TP oring.Ill fitting probe or oring.Under or over oiled piston cup.Leaks.... here is a good test for leaks....Pump you gun up as normal and shoot it over the chrono.Now pump the gun up as normal and let it sit for an hour or so before shooting it over the chrono an compare the numbers.I once had a metal/metal Daisy 880 that was inconsistent on accuracy.. to say the least. Finally I figured it out.... If the gun sat for any length of time between shots it would lose valve pressure.And finally.... operator.. this includes non uniform pumping habits.Slow and consistent wins the race. A short pause at the top of the stroke allows the gun to 'breathe'. In some cases you can even hear the gun take a gulp of air at the top of the stroke.... give it a second to take it all in.
Quote from: avator on January 28, 2022, 01:31:34 PMThere are a few things that could cause that...Just to name a couple..Misaligned valve to tp to barrel.Damaged TP oring.Ill fitting probe or oring.Under or over oiled piston cup.Leaks.... here is a good test for leaks....Pump you gun up as normal and shoot it over the chrono.Now pump the gun up as normal and let it sit for an hour or so before shooting it over the chrono an compare the numbers.I once had a metal/metal Daisy 880 that was inconsistent on accuracy.. to say the least. Finally I figured it out.... If the gun sat for any length of time between shots it would lose valve pressure.And finally.... operator.. this includes non uniform pumping habits.Slow and consistent wins the race. A short pause at the top of the stroke allows the gun to 'breathe'. In some cases you can even hear the gun take a gulp of air at the top of the stroke.... give it a second to take it all in.My velocity is pretty consistent, but I usually shoot pretty soon after pumping. I'll try leaving it pumped for a while next time I shoot.
The barrels on these 362's get dirty fast, I thought my BugBuster took a dive so I put a 4 power on it but that was shooting all over the place too, cleaned the barrel and it's shooting much better, the older Crosman barrels never seemed to get dirty near this fast at all, maybe it's just a breaking in thing hopefully.
Quote from: mentolio on January 28, 2022, 01:04:44 PMQuote from: Spacebus on January 28, 2022, 11:32:54 AMQuote from: Back_Roads on January 28, 2022, 10:50:51 AM 20 post to post pics and web links, greet a few new members and your good to go I will have a 362 totally apart for a good portion of the day, so if anyone wants measurements, or photos, let me know, after some valve porting mods it will not even look like the same gun if all goes as planned I want to know how your valve mods work out. My 362 is a little on the anemic side to start. I'm 150' above sea level where it should make more power than most other people, and I'm measuring right at the muzzle. I'll be shopping for an aftermarket valve, but I'm hoping to have similar results to you!Hey spacebus, sorry to hear you’re not happy with the power. How is your accuracy and consistency? If you’re making consistent power (even if it’s low), and you’re getting good groups, you’re ahead of the game. Should be fairly easy to “power-up” an otherwise decent shooting gun. Might fix with new seals. Bad accuracy, in my experience, is often harder to correct. My 397 sat for 2 years in pieces until I found a good, used barrel and tube for it, and my 1377 has been sitting for two years because every barrel I’ve bought for it so far was junk). You’re getting good groups but pulling to one side or the other right? Maybe a slightly tweaked barrel or uneven crown at the muzzle?Accuracy is great and groups are tight. I attribute any fliers to my own technique or damaged pellets, I only sort my own cast pellets. My velocity is 50-60 fps slower than what other forum members are reporting at 8 pumps. I attached a pic of my chrono data averages. Column A and Column C are with four pumps, column E is my PR900. Column B and D are eight pumps.
Quote from: Spacebus on January 28, 2022, 11:32:54 AMQuote from: Back_Roads on January 28, 2022, 10:50:51 AM 20 post to post pics and web links, greet a few new members and your good to go I will have a 362 totally apart for a good portion of the day, so if anyone wants measurements, or photos, let me know, after some valve porting mods it will not even look like the same gun if all goes as planned I want to know how your valve mods work out. My 362 is a little on the anemic side to start. I'm 150' above sea level where it should make more power than most other people, and I'm measuring right at the muzzle. I'll be shopping for an aftermarket valve, but I'm hoping to have similar results to you!Hey spacebus, sorry to hear you’re not happy with the power. How is your accuracy and consistency? If you’re making consistent power (even if it’s low), and you’re getting good groups, you’re ahead of the game. Should be fairly easy to “power-up” an otherwise decent shooting gun. Might fix with new seals. Bad accuracy, in my experience, is often harder to correct. My 397 sat for 2 years in pieces until I found a good, used barrel and tube for it, and my 1377 has been sitting for two years because every barrel I’ve bought for it so far was junk). You’re getting good groups but pulling to one side or the other right? Maybe a slightly tweaked barrel or uneven crown at the muzzle?
Quote from: Back_Roads on January 28, 2022, 10:50:51 AM 20 post to post pics and web links, greet a few new members and your good to go I will have a 362 totally apart for a good portion of the day, so if anyone wants measurements, or photos, let me know, after some valve porting mods it will not even look like the same gun if all goes as planned I want to know how your valve mods work out. My 362 is a little on the anemic side to start. I'm 150' above sea level where it should make more power than most other people, and I'm measuring right at the muzzle. I'll be shopping for an aftermarket valve, but I'm hoping to have similar results to you!
20 post to post pics and web links, greet a few new members and your good to go I will have a 362 totally apart for a good portion of the day, so if anyone wants measurements, or photos, let me know, after some valve porting mods it will not even look like the same gun if all goes as planned
Quote from: Spacebus on January 28, 2022, 06:52:52 PMQuote from: avator on January 28, 2022, 01:31:34 PMThere are a few things that could cause that...Just to name a couple..Misaligned valve to tp to barrel.Damaged TP oring.Ill fitting probe or oring.Under or over oiled piston cup.Leaks.... here is a good test for leaks....Pump you gun up as normal and shoot it over the chrono.Now pump the gun up as normal and let it sit for an hour or so before shooting it over the chrono an compare the numbers.I once had a metal/metal Daisy 880 that was inconsistent on accuracy.. to say the least. Finally I figured it out.... If the gun sat for any length of time between shots it would lose valve pressure.And finally.... operator.. this includes non uniform pumping habits.Slow and consistent wins the race. A short pause at the top of the stroke allows the gun to 'breathe'. In some cases you can even hear the gun take a gulp of air at the top of the stroke.... give it a second to take it all in.My velocity is pretty consistent, but I usually shoot pretty soon after pumping. I'll try leaving it pumped for a while next time I shoot.Nope, you dont have to wait after pumping, Bill's talking about pausing when you pull the pump all the way out, away from the gun, wait there for a second then slowly close the pump handle, allow the compression to stay cooler and fill the plenum.
I wonder what the twist rate is on these When I looked down the barrel it looked like a faster twist rate than the older barrels but I could be wrong
How many pumps does crosman recommend for this model folks ?
Quote from: Firewalker on January 28, 2022, 11:56:50 PM
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