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1

Sniper's Perch / nickswimsfast's new hopup arms

« on: August 02, 2009, 11:04:25 PM »

NOTE: I am not selling these anymore. (I'm in my senior year of mechanical engineering)

Tuning your rifle to perfection is something I strive for all the time. I'm sure you are looking to do the same thing with your rifles frequently. I've developed two new hopup arms for tweaking Bar-10 rifles, although it could work in other rifles. I designed a new hopup arm on the computer and manufactured several with a CO2 laser.

Required Filing
This filing is required to get a perfect fit in your hopup unit as everyone's is different. It is highly recommended to file the side for a snug fit between shells, and filing the nub may increase performance.

Three Types
I made two versions for the standard DIY type person:
-Standard - this is the base hopup arm geometry. It is much snugger on the shaft than the stock arm, it has a flat prong geometry, and is a good starting place for a replacement or upgrade hopup arm. I recommend testing this arm before using an aggressive arm.
-Aggressive - This is the same thing as the standard except the angle of attack of the slit is higher by a few degrees. The nub is also longer allowing a deeper depression on the bucking. This is recommended for users who are looking to modify the prong shape.
-SCS compatible - This arm has a groove to align and locate an SCS nub for installation. It has the same slit geometry as the Standard arm. (currently untested)

Release
These arms have been officially released. Please understand that these arms are a work in progress, I wouldn't call them perfect. Although, my testing with both arms has shown substantial gains in shot trajectory, and consistency. Note: There is a limited supply for the moment. Pm me if you are interested in acquiring any of these arms. There will be future revisions in the standard and aggressive arms in the future along with an SCS compatible model. On the horizon is hopup arms for other rifles.




http://www.youtube.com/v/lgjwU_fhXoY&hl=en&fs=1&color1=0x5d1719&color2=0xcd311b

2

Sniper's Perch / 1st target 0.33-0.43 BB quality?

« on: May 20, 2009, 08:09:38 AM »

http://www.1st-target.com/targetmain/index.html

They say they have:
0.33 / 0.35 / 0.38 / 0.40 and 0.43 g BB's

Just stumbled across this european brand, says all weights are biodegradable. Anyone ever used them, heard of them, etc..

They claim their tolerances with a deviation of 0.02 which is a little unsettling. (typical is closer to 0.01 in what i've found for most brands)

3

Sniper's Perch / Nickswimsfast's Sniper Projects

« on: May 19, 2009, 04:21:30 AM »

Introduction: I am a tuner and am in my senior year of Mechanical Engineering. I constantly tweak my rifles for near max-performance both for stealth, and max field regulations. This is because I've skirmished with a group about every 2 weeks for the last 2 and a half years.

I don't claim to have the best sniper rifle, so don't be surprised if you have better performance than mine. I merely am documenting it to help others have a basis for comparison, and to understand they may be able to get where I am at. And perhaps I will learn something from you that will help me better myself or my rifles. So feel free to add your experiences!
========================================
Sections:
- Rifle History
- Projects
     x Modified Hopup Unit
     x Clay on Trigger
     x Ghillie suits
     x Gun Wraps
     x Silencing Treatise
     x Concealment BDU's
     x Helmet Camera
     x Gun Camera
     x Spring Force Calculator
- Performance Analysis
     x Groupings
     x Ammo Analysis
- Videos and Links

========================================
Rifle History:
I've owned 2 mp001's before with dee's custom barrels, as well as a TM M16A2, and currently own a echo1 M4. I've worked on UTG MK96, and UTG M324 for friends. I also own the four rifles shown below.

Current Rifles:


-Primary JG Bar-10 - original imported - 2.65 Joules
         x modified hopup unit
         x modified hopup arm
         x nineball bucking
         x repaired stock cylinder
         x Laylax M170
         x Laylax Zero-Trigger w/ orange piston and air brake
         x Replaced o-ring with #13
         x Laylax PSS10 Cylinder Head (lathe ported further)
         x PDI 6.01 430mm barrel
         x Homemade barrel stabilizers
         x Teflon taped bucking, and cylinder head threads
         x Lathe turned custom steel spring guide
         x Replaced almost all screws with new high grade ones


- JG Bar-10 G-spec - (max silence build) - 1.5 joules on optimal round
         x mock mock mock mock mock mock mock suppressor
         x Packaging foam stock
         x #14 o-ring
         x full air-brake
         x teflon taped bucking, and cylinder head threads
         x Modeling clay trigger assembly


- JG Bar-10 - friends broken rifle purchased and fixed - 1.7 joules on optimal round
         x Lathe ported Cylinder head
         x repaired trigger


-TM Gspec (stock-unmodified)

4

Sniper's Perch / Video Footage 375 Foot Shot

« on: May 14, 2009, 11:57:15 AM »

Highly recommend watching the HD versions on youtube.

I shot these videos to demonstrate what the maximum range i could hit a target with my sniper rifle. I also did this to prove that shots beyond 300 feet could be done, and with a field legal rifle no less.

Information for skeptics
I took two videos, one from the gun, and one from the target. There is interruption in the videos because a civilian rode up on a motorcycle. With the help of my friend I measured out 100' increments with a store bought 100' rope, all the way out to 400 feet, then measured back 25' increments with a tape measure. So I'm gonna say it is 375' +/-5 feet with confidence.

My friend was spotting for me ensuring that the hits, weren't simply bounces or ricochets hitting the target (as that did happen on a couple attempts.) By no means was this an easy shot, it took adjustment for wind, hopup, breathing, and consistency in the ammo. For this reason I took a LOT of shots, to make this one land cleanly, and did not include the boring footage.

http://www.youtube.com/watch?v=KDIDKJeib2g

http://www.youtube.com/watch?v=GBiL0C0nClU

Conclusions
It's a fun challenge, but not realistic for gameplay. It is impractical to be spamming like that in a game to land a "massive shot." What i did find from shooting at this range is windage consistency is not as difficult as vertical consistency. I "feel" I had an approximate 10 foot windage grouping (that means 5 feet in either direction of the target.) I also "feel" I had a 40 foot vertical grouping (20 feet in front and behind the target) based on hopup, angle of the rifle, and several other variables that i may or may not of had control over. Tuning for hopup consistency I believe is the secret to making your rifle accurate at long ranges, as you have to drop your shot in on the target, rather than simply aiming at it.

This experiment was in ideal conditions for max range shooting. Tree protected shooting lane (Low wind), low density of air, spotter for my shots, lots of time, lots of shots.

Trajectory Calculator
The trajectory calculator Noobie used is fairly accurate for my rifle's setup as well. Here is the results that I calculated:
http://img222.imageshack.us/my.php?image=375footshot.jpg

The only thing that doesn't add up with the calculator is the projected time of travel. The calculator indicates almost 4 seconds of travel time. From the footage I have estimated a travel time of about 3 seconds. There are only two things that I can come up with to account for the difference.
1) The calculator is wrong - too many assumptions and approximations to hold it to this accuracy.
2) Since it is at 6000 feet and the density of air is substantially less the round should decelerate less than it would at sea elevation.

Thoughts?

5

Sniper's Perch / How to efficiently pull a high powered bolt

« on: May 01, 2009, 04:21:22 AM »

I had a couple questions as to why it appears "easy" for me to cycle my bolt. To answer these questions, I made a video to show, and convey points that I believe "make it easier" to cycle your bolt.

http://www.youtube.com/watch?v=k_iLWZ-8U9M

My rifle has a broken in Laylax M170 spring. I wont claim to be exceptionally strong just normally fit. For reference, at the moment I can do about 45 pushups and 8 pullups. I weigh in at about 175 lbs.

Enjoy.

6

Sniper's Perch / Laylax Zero Trigger video (how it works)

« on: April 07, 2009, 11:07:47 PM »

I just uploaded a video showing the internals of the Laylax PSS10 Zero Trigger showing how it works; just in case you are wondering, or need to rebuild yours.

By the way, the high quality version looks better:

http://www.youtube.com/watch?v=lfSM2MVJq7w

7

Sniper's Perch / What type of O-ring replacement?

« on: September 10, 2008, 06:33:05 PM »

There was a time when we were discussing replacement o-rings on the forums, and I recall TCF or someone mentioned a different low friction material that sounded like velcron or viltox.... etc... I cannot find it for the life of me even with the search feature.

I'm looking to purchase a replacement o-ring for my orange high pressure piston. I have already gone to home depot and ace hardware stores to try and purchase a good one, they don't have a large enough selection to find the "perfect" size.

8

Sniper's Perch / Removing Airbrake necessary?

« on: November 28, 2007, 07:14:29 AM »

Is removing the airbrake, or shortening it on a Laylax High Pressure Piston necessary for my setup to get slightly above 500 fps on .2's ?

Current Setup:
Bar-10
Laylax Zero Trigger with High Pressure Piston (orange)
6.01 mm dees custom tightbore
king arms air seal hopup bucking (like nineball)
Custom metal spring guide
an OLD m150 spring from a friend

Background:
I dont' have a chrono, but based off of the coke chrono I am probably shooting around 460-480 fps. I should mention that I am using the laylax zero trigger provided o-ring as it yields better FPS than the old piston's o-ring. I went to the hardware store and purchased several to see which worked best. I am probably going to purchase some more o-rings from a distributer with a wider selection until I find one with the perfect compression, or mod one with the kerosene trick.

I am reluctant to cut off the airbrake as it is a permenant thing, and it increases strain on the internals, vibrates the gun more, makes more noise, etc... I already cut it down on my stock piston and regretted doing it as much as I did.

Questions:
1. Do I need to purchase a new m150 (it appears to be almost an inch shorter than my other springs)

2. Will I need to shorten or remove the laylax air brake to hit around 525 fps? For your guys who have ever ran a gun over 500 fps, did u have or keep the airbrake on?

3. I have heard that the laylax high pressure piston airbrake is held on by a "grub screw" that is supposedly is removable, but it doesn't appear removable to me... any info on this is appreciated.

9

Sniper's Perch / Installing a Zero Trigger to Bar-10

« on: October 28, 2007, 11:47:44 PM »

I know someone who will sell me a lightly used Zero Trigger, I was wondering how difficult would it be to install a Laylax Zero trigger into a Bar-10. I only ask because I have heard of people having trouble installing them, and having to bore out the stock a bit to make it fit. I was hoping someone might have an answer before I go and drop the money.

10

Sniper's Perch / Spring Pull Strength and FPS

« on: April 26, 2007, 05:43:25 PM »

Why is there such a huge difference in spring pull between guns, but seemingly only a 100 fps difference?

I have an mp001 and it seems to me an effortless pull and cock compared to other guns. My friend has a gspec with a m150 in it and its insanely hard to cock, I can't even imagine trying to do that while prone. My mp001 shoots around 440 fps. The m150 I believe is used for guns to get around 550 fps.

Why is there such a huge difference in the spring pull for these two guns? Spring lengths? Compression? Is it possible to get a 550 fps gun without such an insane pull?

11

Sniper's Perch / Optimum Piston + Cylinder Allowance Tolerances

« on: April 18, 2007, 11:24:42 PM »

My last Topic was deleted, probably due to a vague subject title. So if you delete this topic, please pm me why, and how I can correct it. On to the topic...

I have an mp001(It was a lemon so don't base your assessment of the mp001 on this, it's a great gun), I have been messing with the spacing between my piston and cylinder. Without an o-ring the tolerance between my cylinder and piston is about a total of 0.05"

With an O-ring I have exceeded the allowance by a little bit making piston a tight fit, that makes perfect compression. (By perfect I mean that if you put your finger on the nozzle and fire, the piston will not budge at all.) The one drawback to this is that it is so tightly fitted that it reduces the velocity that my gun is capable of, conversely it makes my gun almost inaudible. (shoots 340 fps with the tight o-ring on)

So today I decided that I would try the piston without the o-ring I had installed at all. (my gun did not come with an o-ring stock - which is why i believe it is a lemon) After closing up the cylinder and testing, I was getting about 200 fps. Clearly that 0.05" of space is too much of a gap to maintain enough compression to be effective.

That being said, what kind of freedom of movement/compression do you have with your gun? (I don't care what kind of gun it is) Maybe try firing with your finger on the nozzle, and see if it slows the movement of your piston, or doesn't allow it at all?

While I was looking at my AEG's O-ring and piston, I noticed my o-ring is free to move along the piston in a groove, so that when you push it forward, the o-ring slides to the back of the groove and completes a sort of temporary seal. I was wondering is this "play" with the o-ring necessary for optimal piston movement, and compression?

If you have any ideas an the optimum, piston/o-ring spacing or setup, please let me know!