Disco SSG thread

[ped]

challenger/p-rod hammer is a drop in unit in all the crosman 22xx and disco guns and will work with std triggers

[Rivers3Plinker]

Steve, I just re-read your post and it looks like you have to have a MROD trigger for the challenger hammer to work in a Disco. Is that correct. I have the regular Disco trigger group.

Indeed I have the Mrod Gen1 / Challenger trigger group on my Disco using a Prod hammer weight.
I also put the Challenger guard on my trigger.

As far as I have been aware, the OEM Disco trigger uses the same style of sear engagement as the 13xx trigger group and requires a weight with a notch in the middle for the sear to catch. Trigger groups that engage the face of the weight are Mrod, Prod, Challenger, and 1701P.
The weights for these triggers don't need the notch but it can be used with them. If you use a notched weight, the notch can strike the sear and damage it over time after shooting. I have built a 13xx using a filled weight and later an upgraded solid stainless weight with a 1701P trigger and it was very nice.

Note the challenger weight on the left and the Disco on the right.

That said, the Challenger trigger upgrade while pricey in my opinion is very nice, and a much better trigger than the OEM Disco. I even had the brass upgrade for awhile which was much better. For the cost of the whole Mrod trigger conversion I could have bought a 392.

So if you go this route using the Challenger weight, be aware the potential issue. I've never tried using a challenger weight with 2260 trigger.

[rsterne]

The notch (waist) in the middle of a Disco/22XX, or a 13XX hammer serves NO useful purpose (except to hold the hammer off the end of the valve if you pull it back just a small distance).... The sear does NOT engage there when the gun is cocked, it engages on the front of the hammer, in exactly the same place as does the PRod, Challenger and 1701P hammer.... The MRod hammer also engages on the front....

If you use the PRod or 1701P trigger group on a 13XX, Disco or 22XX, you must use the corresponding hammer, WITHOUT a notch in the bottom, or fill the notch in, or you will have to pull the trigger in order to cock the gun.... I have made many cylindrical hammers for 13XX, 22XX and Discos, for use with either the standard trigger or an MRod trigger, and I can assure you that they work perfectly.... The notch (waist) is NOT required....

Bob

[Rivers3Plinker]

The notch (waist) in the middle of a Disco/22XX, or a 13XX hammer serves NO useful purpose (except to hold the hammer off the end of the valve if you pull it back just a small distance).... The sear does NOT engage there when the gun is cocked, it engages on the front of the hammer, in exactly the same place as does the PRod, Challenger and 1701P hammer.... The MRod hammer also engages on the front....

If you use the PRod or 1701P trigger group on a 13XX, Disco or 22XX, you must use the corresponding hammer, WITHOUT a notch in the bottom, or fill the notch in, or you will have to pull the trigger in order to cock the gun.... I have made many cylindrical hammers for 13XX, 22XX and Discos, for use with either the standard trigger or an MRod trigger, and I can assure you that they work perfectly.... The notch (waist) is NOT required....

Bob

Hey Bob,
Thanks for clarifying for and helping me understand as well.
Poster ped - I wasn't doubting your advice, I'd just never heard of using non-waisted hammers with these triggers and obviously misunderstood the sear engagement.

[thesandman]

I was thinking the waist allows air movement(vent) from hammer foward travel thru notch to prevent compression and loss of hammer speed. It has to go somewhere.

[Buldawg76]

Prod trigger assy from crosman is only 36.50 and Mrod trigger assy is only 48.93 with 4 buck flat rate shipping for both so IMO they are not pricey at all for what you get as I am building a disco tubed, 3000 psi, challenger hammer,spring and RVA, Prod triggered, 1399 stocked, steel breeched, daisy Avanti 20 inch LW barreled, FT gun right now and have less that the price of a new disco in it so far and fully expect it to shoot circles around any disco as well as get twice the shot count.

Mike

[mooseslayer]

woohoo...springs are here. Four 10 inch .312 OD in .037, .041, .047 and .055 wire thickness. Hopefully I will have time to play this weekend.

[Airgun.Sniper]

Im ready to see some results


 Jay

[mooseslayer]

I forgot...pictures or it didn't happen...

[Buldawg76]

Waiting for results on testing.

Mike

[moorepower]

it's made from low grade steel so to re harden you would have to use kasenite or similar
the carbide burrs are a few quid
just to see I took a stock disco hammer and drilled it m5 and a 8mm counter bore to sink the head of a m5 bolt iturned down to 7.5 mm
took about 15 mins to do

.  Does this protrude when cocked?

[Buldawg76]

It has to as I see no other way for the spring to be compressed without it protruding from the front of the hammer and when fired the hammer moves forward on the guide until they hit the valve stem as one unit with zero preload behind the hammer after released by the sear. IMO

Mike

[mooseslayer]

Ok...some preliminary testing with new springs. There are so many factors that can vary the results so I started with a goal of about 800fps with jsb 15.89 to get me about 22 -23 fpe on disco .22
The .037 springs too light...was in high 600fps range with a 3" spring so didn't even shoot strings.
The .041 spring I did a couple quick tests which were similar to my first ones with .040 so I decided to leave and test more later.

On to the .047 springs...started about 3" long so lots preload, very hard to cock mid  800fps but descending string, so start cutting coils and trying until I got just over 800fps  and strings not descending. I ended up with 2.35 inch long spring and started testing.
Test 1 - fair amount of preload, close to coil bind, small gap 2300 - 1400 JSB 15.89 2.35, .047 spring

1-813

[mooseslayer]

oops...try again.

Test 1 - fair amount of preload, close to coil bind, small gap 2300 - 1400 JSB 15.89 2.35, .047 spring

1-813   11-821   21-806
2-816   12-819   22-805
3-818   13-820   23-800
4-821   14-821   24-802
5-820   15-819   25-793
6-819   16-814   26-788
7-813   17-810   27-787
8-819   18-818   28-782
9-821   19-809
10-821  20-811

[mooseslayer]

Test 2 - same preload, dial in nut on SSG to create bigger  gap 2300 - 1500 JSB 15.89 2.35, .047 spring

1-795   11-809   21-807
2-797   12-812   22-807
3-800   13-813   23-799
4-796   14-814   24-801
5-802   15-815   25-795
6-808   16-808   26-792
7-808   17-807   27-788
8-805   18-809   28-786
9-807   19-806   29-784
10-807  20-805  30-777

so just changing the gap can make a difference

[mooseslayer]

Test 3 - dial out nut 1 more full turn so bigger gap 2300 - 1400 JSB 15.89 2.35, .047 spring
Note ...all my adjustments one full turn on bolt (preload) and nut (gap so there is a lot of room for minor adjustments to meet your specific goal. Changing the gap here didn't do a lot.

1-792   11-800   21-803
2-798   12-803   22-805
3-808   13-814   23-795
4-799   14-815   24-802
5-801   15-809   25-803
6-798   16-799   26-790
7-793   17-801   27-792
8-804   18-796   28-786
9-795   19-800   29-774
10-799  20-808  30-768

[Dairyboy]

Your 2nd string is definitely the best. 29 shots with a 3.8% ES.

[mooseslayer]

Test 4 - dial 3/8 bolt out one full turn easier to cock, less preload, small gap 2300 - 1400 JSB 15.89 2.35, .047 spring
Less power but more shots...I kinda like this string and near my goal and very consistent.

1-774   11-776   21-779   31-777
2-768   12-783   22-778   32-777
3-775   13-775   23-778   33-776
4-772   14-780   24-779   34-777
5-771   15-782   25-779   35-768
6-780   16-772   26-780   36-771
7-771   17-783   27-779   37-764
8-774   18-782   28-776   38-763
9-783   19-786   29-783   39-761
10-777 20-785  30-777   40-757

[mooseslayer]

Test 5 - same preload as #4 but 1 full turn gap 2300 - 1400 JSB 15.89 2.35, .047 spring

1-771   11-775   21-782   31-768
2-773   12-782   22-787   32-768
3-783   13-781   23-782   33-765
4-770   14-777   24-782   34-764
5-778   15-782   25-783   35-758
6-774   16-783   26-778   36-760
7-779   17-784   27-777   37-754
8-774   18-783   28-770   38-747
9-773   19-778   29-777
10-772  20-783  30-778

[mooseslayer]

That's all I have time to test for now, but same spring, just change preload and gap. I will try one more turn out on bolt if I have the room, which will probably drop me closer to 750fps and then decide whether to clip another coil  on the .047 spring and test some more. Then a quick try with the .055" spring, which I think will be too strong, and back to testing the .041 spring.