After replacing the FX OEM transfer port with Ernest Rowe dual transfer port how much fps increase should I expect to see on a gen 2 Crown without retuning?
Tuning Ernest Rowe dual transfer port
- Thread starter perazzisc3
- Start date
you wont see anything unless you increase power from my experiance i actually lost fps with same tune
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didnt was shooting a 380 crown to see what it woud do 700 might be different story as those are made for slugs heavy pellets
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I just installed an Ernest Rowe transfer port on my .25 cal, 700mm Impact M3 and lost 30 fps with the same tune. Was shooting 960, now shooting 930 fps. Back to the factory port for me.
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I got about 30 fps when I switched to I suppose it could depend on barrel length and reg settings
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Just to clarify… I lost 30 fps using the ER port. I tried the pin probe and only gained 10 fps back. I switched back to factory xfer port. With the factory port my gun shoots the same speed between pellet probe and pin probe so I just use the pellet probe. Currently shooting JSB Knockout MKII’s at 960 fps.
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I find losing 30 fps quite interesting. Did you change any orings or anything at the same time? A larger hole causing a loss in velocity seems odd. Not arguing because results are results. Just wondering if there is another culprit.
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Depending on where you buy, I’ve noticed the rim where the alignment index notch is on the brass TP is longer than like the Huma versions or even the old factory fx TP’s that just came with a single hole.
If you’re not careful because of that difference, you risk not having the transfer ports aligned between the pellet probe and the brass TP. This will happen for sure if you mix and match one makers probe with another’s TP. With the impact one has the luxury of adjusting the pellet probe depth for alignment via the cocking rod, but other models like wildcats, Mavericks, etc there is no adjustment.
With that said, anymore I just buy both the probes and TP’s from Huma, or just port out the original factory pieces
If you’re not careful because of that difference, you risk not having the transfer ports aligned between the pellet probe and the brass TP. This will happen for sure if you mix and match one makers probe with another’s TP. With the impact one has the luxury of adjusting the pellet probe depth for alignment via the cocking rod, but other models like wildcats, Mavericks, etc there is no adjustment.
With that said, anymore I just buy both the probes and TP’s from Huma, or just port out the original factory pieces
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In regards to the Impact, I tried both the FX pin probe and the Huma one...both ended up for me not very robust. I ended up using the Ernest TP and an NSA probe.
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Take a deep breath and blow as hard as you can through a 1/4 inch pipe.
Now take the same breath and blow through a 1 inch pipe....... see the difference?
But if you can increase the amount of air through the 1 inch pipe you can send a larger projectile further faster.
Now take the same breath and blow through a 1 inch pipe....... see the difference?
But if you can increase the amount of air through the 1 inch pipe you can send a larger projectile further faster.
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I did notice the ER port has longer index notches and I did play around with seating depth, but found no position that got me back to factory performance.
I know that port and probe alignment play a big factor in efficiency and performance. Interestingly, I’m not able to get my factory port and probe lined up perfectly. I need my probe to seat further into the transfer port but if I shorten the cocking linkage I cannot insert the magazine because probe sticks out. I’ll post some pics later to illustrate this better, but curious if anyone else has this “problem”?
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