New MB550 Adjustments

Thread starter #1
Picked up 5 dozen MB550 closed jaw traps from Brian at Southern Snare and Supply in Hortense GA yesterday. Along with 5 doz chain stakes. Great guy to deal with. He met me in Alma to save me shipping costs and time.


Unboxed. Time to go to work.


There is no such thing as a “ready to set, out of the box trap.” All traps should be checked for pan tension, pan creep and pan level. The MB550s are close to ready out of the box, but need a little tweaking. The first thing I do is trim the spring pins down to about 1/2 inch. This makes the trap bed easier. You can also bend them down if you would like. I prefer to trim them.



Next on the agenda is to check the trap for pan creep, tension and level. I start by setting the trap in the night latch and slowly pulling the pan down. If the pan travels at all before the trap fires, this gives the animal a chance to feel the pan move and refuse to commit to the set. Pan travel is adjusted by shortening the dog flat. The dog flat is the part of the dog that the pan rests on after it clicks into place. This flat is often times too long and allows a good bit of pan movement before the trap fires. A long flat can also increase pan tension.



The gap between the pan and dog is wahat causes the creep. I file the dog flat shorter to take out the gap. This produces a very crisp firing trap that averages 3 lbs. Take your time filing. You can remove too much and the trap will not set.


After making these adjustments, I will attach the chain stakes and degrease the traps. I normally run them for a few weeks to get a light rust on then. Then I will boil/dye. I do not wax my traps.
Very good information. I do pretty much the same, but I don’t trim the spring rods. I occasionally will turn a two coil into a four and don’t find them too problematic even if I don’t.

Mark K

Senior Member
Can someone put this in the sticky threads? Good info to know. Some of us look to this site to learn from the more experienced trappers.


Senior Member
Biggest thing with the spring pins for me is they can get caught in a chain link and render your swivel connected to the trap useless. The way I dig my trap beds the pins would actually help me support the loose jaw side. I trimmed mine to half an inch though after having a few get tangled up.


Senior Member
Aside frim clipping the pins I still like to add a another swivel mid chain. I also put a quick link on the end with a double stake attached to it. I close the j hook on the double stake in a way I can easily slide the double stake off the quick link. This allows me to switch easily from running rebar to running cable stakes.