Reply With QuoteMore reading here too...
http://www.airgunbbs.com/showthread....or-more-spring
They dare not speak his name in hushed tones
Having fallen in love the Brummie Stingray .22, I think I could be happy with that rifle and nothing else.
The Stingray has the TW Chambers premium kit: cut-down Titan spring, metal top hat and spring guide.
It still thumps a little but it is so pleasant to shoot and very very quiet.
All the same, I've had the itch for a .177 and ideally the same rifle just the smaller pellet size.
Having bought that recently advertised Xocet (needing some love), I've found it feels incredibly harsh.
The snap of the rifle by my ear gives me a headache, and the recoil was unpleasant.
Had a scour through the old threads, and especially this one:
https://www.airgunbbs.com/showthread...oil-177-vs-22/
Since it's internally similar to the Stingray, I compared springs and found the original Stingray spring was idental just a couple coils shorter. Popped that spring into the Xocet and found it had less recoil, but the snap was still loud and unpleasant. On the cheap airsoft chrono I'm getting around 9.5fpe and spread of around 10fps with the RWS Hobby wadcutters, with the shorter Stingray spring. Had I checked the original spring I'm assuming it was running pretty close to maximum 12fpe.
I've ordered the TW Chambers kit, and I'm hoping the top hat and quality spring guide will help smooth the shot cycle.
So, the conundrum. Following on from various reading online, the question in my mind is, if the recoil is a symptom of the spring and you can preload a spring with washers and weights, would that make a smoother shot than the additional coils to the same fpe?
They dare not speak his name in hushed tones
More reading here too...
http://www.airgunbbs.com/showthread....or-more-spring
Registered User
The answer is yes but its a black art and will change from one springer design to another! A 177 will never shoot as nice as a 22 im afraid.
Plinkerer and Tinkerer
They dare not speak his name in hushed tones
As I suspected, based on the reading.Originally Posted by maximus
TW Chambers kit arrived.
Scragged the Titan #7 spring for around 18 hours overnight.
In the mean time, opened up it looked like the piston seal was quite new. Hard and a little bit shrunken but undamaged. Replaced it since I was in the rifle anyway.
The piston didn't want to move too freely inside the barrel, so I manipulated it back and forth to get the seal and surface to marry. I suppose in many ways the pistol edge was being ground as the chamber was being polished. All the same it began moving smoothly with a small degree of positive resistance.
Released the spring from the threaded rod this morning.
A few coils cut off, ends filed to a round, metal top hat fitted.
Total spring length including top hat equal to original spring without top hat.
Having rebuilt, I forgot about the inevitable dieseling for the first dozen or so shots.
Made a bit of an error in judgment and aimed at the targets, instead of into the scrap piece of carpet on top of the mud.
Bloody hell what a bang! The smoke was like a musket fire!
Luckily this was with lightweight RWS Hobby's so there was as little backpressure as possible.
Once the rifle stopped tattooing the carpet and quietened to a normal crack, I grabbed the cheap chrono and fired some RWS Hobby pellets.
RWS Hobby 7gr / 0.45g
857.1
854.7
852.9
843.4
842.8
859.5 (High = 11.49fpe)
849.9
841 (Low = 11fpe)
846.9
Avg 849.8 = 11.23fpe
The pellets are very snug, and it's difficult to set the skirt flush, so I may look at countersinking the end to aid loading.
The variation in fps correlated to the pellets sitting flush or protruding fractionally.
Once it settles down and the last of the excess lubricant has escaped, I'll re-chrono with two or three pellet weights.
I think it may need the spring trimming a little more.
Definitely smoother and less harsh with the top hat.
The action is still a bit noisy compared to the .22, that typical .177 'crack'.
Very little kick/boing now, but more of a thump, as I'd hoped.
I'm loathe to drop the power too far below 11fpe if there is no noticeable gain in shooting cycle characteristics.
They dare not speak his name in hushed tones
So, something didn't feel right, and I was getting inconsistency when using at the outdoor range. I expected some variation with unsized pellets, but some were dropping way more than others. The above numbers it must have been going very fast with the excess lubrication.
After another noisy bit of dieseling after it should have calmed down, I assumed maybe the piston seal got nicked when installing.
Also possible the barrel wasn't as clean as I thought (hence difficulty moving piston back and forth on install).
I stripped and checked and unfortunately that happened to be the case. Ordered a new seal
Finally got around to rebuilding it with a new seal this week.
The barrel location pin had a tiny bit of play, allowing the barrel to wobble the absolute tiniest amount, but noticeable. Shimmed this tight, and now the barrel is rock solid when closed.
New numbers look a lot more realistic.
Sized pellets to 4.50, steady average 814fps/10.3fpe with RWS Hobby Sportline 7gr / 0.45g.
Spread less than 20fps, for the most part around 10fps across 15 pellets.
Highs with pellet skirt protruding, lows when pellet sitting deeper into barrel.
Need to take it to the range and give it a tin of pellets to see if any inconsistency remains.
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