Author Topic: dippin griz / dklic6 Marauder Tune (Read 5426 times))

dippingriz · « **on:** October 31, 2015, 01:04:57 AM »

Howdy all,

First and foremost: Thanks to all that have already contributed to the forum. I and many others have learned so much from your experiences.

Here is what I want to achieve:
- Educate and compose a repository of information for the Marauder .25 cal
- Find a tune that suites me aka 16 shots @ 850 - 900 AVG fpd with the capability to shoot out to 100y
- Common sense view / validate solutions that can be facilitated through your local Home Depot / Lowes / Ace etc (let's not drop money on what we don't need to)

Finally: Have fun and enjoy the science / process!!!

- Dave

Here is the first video of the set up:

Disclaimer:
I've been right and I've been wrong. If I am way off about something, please let me know. Integrity of data is important to me!

Jmorris · « **Reply #1 on:** October 31, 2015, 12:36:04 PM »

Hold your cell phone sideways and your video won't look like it was shot with blinders on.

dippingriz · « **Reply #2 on:** October 31, 2015, 02:43:50 PM »

Thank you, that will happen from now on.

Regards

Tater · « **Reply #3 on:** October 31, 2015, 03:00:48 PM »

Nicely done video. John's suggestion is all I would change.

Tweeter · « **Reply #4 on:** October 31, 2015, 05:43:11 PM »

Great video! Can't wait to see how it turns out.

dippingriz · « **Reply #5 on:** November 02, 2015, 09:48:47 PM »

Thank you for the words on encouragement all! I will try to get an update out this Friday or Saturday. The current video on deck is already shot with the phone in a more appropriate orientation.

Dave

dippingriz · « **Reply #6 on:** November 18, 2015, 11:19:03 PM »

Link to chrony set up:

Howdy all!

I've been busy lately so the project had to take a place on the back burner but I got to get about 4 hours in today.
No video was shot due to shooting strings over a chrony and watching me pump is really boring stuff. Let's get
straight to it (You will see the adjustments made in the pictures):

Initial (factory) tune:
Ugly curve, we'll fix that

Set 1

Set 2

Set 3

@ RayK
Thank you for the compliments on the property and I knew there would be some fellow archers lurking around
the airgun sites. Your starting point was spot on for where I wanted the tune to go.

So....where do we go from here?

I would like to get my dope set up, do some hunting, and get the camera set up. In regards to the camera...I will have to do some
thinking about lens zoom levels and mildots. Videos this weekend maybe?

Thanks for sticking with me folks.

Dave

GD Giles · « **Reply #7 on:** November 19, 2015, 12:25:27 AM »

Awesome work. Looking forward to your progress.

dippingriz · « **Reply #8 on:** November 22, 2015, 10:27:00 PM »

New video of the pellet trap. By the time I got done shooting it was too dark for the high speed camera to pick up the pellets.

Here is the mentioned duct seal from lowes:
http://www.lowes.com/pd_13591-12704-31-601_

dippingriz · « **Reply #9 on:** November 23, 2015, 05:49:52 PM »

I had to take advantage of the beautiful weather we have today. I have some really sad news (for me):
While cleaning up I noticed my Marauder was just about 3000 psi...could have sworn I filled it before putting all the equipment away. After editing the videos I'm down to 2900 psi...I suspect a leak and I'm going to assume it's the gauge. I'll let it sit for a while to see if I'm crazy and then soapy/bubble test the gauge. Hopefully I can tighten it down or I will be ordering another gauge off of McMaster Carr. Kind of a let down after some fun shooting and tedious tuning but if that's the biggest problem I run into today I'm going to say it is still a great day.

Other thoughts:
I really like using the camera but it's a royal pain with this mount:

It does not hold very tight and the rubber that holds onto the scope is already coming off. Not worth $53 dollars. If anyone else has a better solution I would love to know!

Videos:

Thank you all for support thus far!

GD Giles · « **Reply #10 on:** November 23, 2015, 08:33:38 PM »

Cool stuff! I like the trap you made. I'm late to the conversation but I'm guessing that's what you use indoors next to your bench for chrony work and such?

dippingriz · « **Reply #11 on:** November 26, 2015, 03:02:14 AM »

Yes Sir, that box is for 100y and under + chorny work.

Habanero69er · « **Reply #12 on:** November 26, 2015, 07:06:54 AM »

It would be interesting, at least to me, to see how much that target box weighs now & then again in say, 2 yrs. There was a lot of lead in your wooden target box. By the way, good work on that tune. Set 3, string 2 looks pretty good.

dippingriz · « **Reply #13 on:** December 14, 2015, 06:42:41 PM »

Quote from: Habanero69er on November 26, 2015, 07:06:54 AM

It would be interesting, at least to me, to see how much that target box weighs now & then again in say, 2 yrs. There was a lot of lead in your wooden target box. By the way, good work on that tune. Set 3, string 2 looks pretty good.

I am curious to see how much fodder it retains as well. I still need to add some more because I'm getting some pass through already!

dippingriz · « **Reply #14 on:** December 14, 2015, 07:26:31 PM »

Pellet Testing was today's theme. tl;dl JSB King's are exactly what was needed

Still in the works:
- I am waiting to do a follow up video after the air tank comes in for the 80y video
- bedding and polishing internals. Most likely a layer spring removal as well
- My stock is getting beat up in the deer stand and rolling around in truck so I'm thinking a refinish is in order (black cherry because that is what I have in the garage)

Thanks all!

dippingriz · « **Reply #15 on:** December 18, 2015, 01:39:48 AM »

Created a pillar and starting the bedding job:

Tweeter · « **Reply #16 on:** December 18, 2015, 06:15:40 AM »

Nice work, is the soft bedding supposed to eliminate any poi change that happens when the air tube contracts and expands? I know, I know, I could just google it but I'm lazy...

dippingriz · « **Reply #17 on:** December 18, 2015, 08:48:34 PM »

Yes sir. The pillar provides a repeatable tension in conjunction with floating the airtube off the stock. Resulting in tension and psi apathy from the rifles action. As long as I stay in the rifles tuned psi I should have better groups.

dippingriz · « **Reply #18 on:** April 16, 2016, 04:38:20 PM »

UPDATE with more SSG shenanigans

Howdy all,

You know when you get to a point during a tune that you just need to quit at? That happened today. I was not able to get close to my 850ish 4 mag tune with the SSG installed so I'm accepting (for now) 800fps 4 magazine tune at 3000psi starting point until I have another morning free.

"The barn set for tuning"

Tuning Factors:
VMS wide open
SSG turned in to 6 turns from zero (all the way back)
68 degrees 80% humidity

"Set 1-1"

6 turns from 0: No real bell curve, trash string and higher FPS than I thought would be acceptable.

"Set 1-2"

Back off 1/2 turn. Too low but not a terrible string

"Set 1-3"

Increased again 1/2 turn to confirm last numbers and I had this erratic string that I couldn't explain. 2 more string were shot after this resulting in the same unpredictable FPS.

"Tear Down"
My spidey-senses told me something was askew...so the marauder ending up in pieces until I discovered this in the end cap:

You are looking at the backing cap / buffer zone of the SSG that has slipped sideways and is not providing repeatable spring compression. I'm assuming when increasing and decreasing the spring pressure the cap slipped sideways. FYI for those that have a steve in NC kit do not go past 8 turns or the cap will displace.

"Problem fixed and rifle back together"

There are still a few spikes in FPS, but for now I have to walk away from the project until I think on it some more.

Plans for the future:
- Porting of the valve and switch to freezer tube.
- More time tweaking string...I really don't want to increase fill pressure

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dippin griz / dklic6 Marauder Tune

Author Topic: dippin griz / dklic6 Marauder Tune (Read 5426 times))