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ZipSnipe · Veteran Member

Ok I learned recently that the breech really should be called a receiver.

And here is what I got so far

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I got the Marauder clip to stay in the receiver BUT I need to do this

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So when you push the pellet thru my down part of the slot needs to be milled out more. Not what I really wanted to happen but it is what it is. Remind you my template was the original plastic receiver that I modified as I went.

I also had to do my bolt like this

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I am going to probably scrap this bolt and make one out of some titanium that I have. Brass and aluminum are not the best for having metal sliding against each other .

Man now I know how Dogon must have felt like making his receiver.

rsterne · Moderator

Nice job so far.... How are you going to make the flat breech (sorry, I refuse to call it a receiver) fit the main tube which is round?.... or are you just going to rely on the bolts to keep it straight?....

The downwards part of the bolt slot needs to be vertical or even sloped backwards on the back edge or the bolt handle will pop up on firing from the air pressure pushing back on it....

Bob

Robw · Veteran Member

Very nicely done! I am anxious to see the finished product.

Oh, and I appreciate how you refer to parts by their correct
terms. It leads to less confusion.

I have a question though. If some people mistakenly refer
to the receiver as a breech then what do they call the actual
breech? You know, the end of the barrel that you put the pellet
in. What do they call it, the second breech or maybe the
other muzzle or pellet end of barrel? Just curious.

ZipSnipe · Veteran Member

Hey Bob if you look real close at the first pic you can barely make out the radius cut in the bottom.

The breech is in the receiver or as I was told its the loading part of the barrel.

Ok both receivers are working now. Put the clip and and it pushes out the pellet into barrel and locks the bolt. Now onto the hammer cocking pin as I have to make a new one because this receiver sits higher than the original.

I am also going to make a longer transfer port tube, hopefully be able to test fire tomorrow.

rsterne · Moderator

I would call the breech end of the barrel the chamber, and in front of that, the taper into the rifling the leade.... Perhaps this is incorrect, but if you try and purchase a steel receiver from Crosman, they won't know what you are talking about, they call it a breech, and I'm just being consistent with common usage in airguns.... Here is ONE definition I found....

ZipSnipe · Veteran Member

Yeah I forgot who told me that it should be receiver but from this day on we will just call them breeches just for the sake of not confusing people including myself.

Ok got the transfer port done now onto the cocking pin

ZipSnipe · Veteran Member

Aahhh Research and Development!!!

Ok getting there. I made a new bolt from the titanium I had. Extremely tough to machine if you don't have good carbide cutters.

If you look in the pic I need to turn the groove down where the o-ring sits so that the bolt can go into the barrel a little more.

Then this creates another problem where the bolt handle locks down is of by several thousandths. I conjured up a quick fix for this , I will simply just add a sleeve over the bolt handle and this will allow it to lock down. That will be my project for today.

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It was funny I had finished the bolt this morning got it all put together minus the probe o-ring. All look good and was starting feel proud. Then I put the o-ring on and seen I still had more work ahead of me.

ZipSnipe · Veteran Member

A little more progress or shall we say higher learning. This is a scab I made to fix my bolt handle notching mistake, however this one is going to be extended to the clip opening as there is a gap in front of the bolt handle that when you go to load the pellet it allows it to be pushed further in but then the o-ring hangs up in there on your next cycling of the bolt. So another new scab must be made so that the bolt handle has a nice snug place to hang out without extending to far into the barrel.

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Alstone · Moderator & Site Supporter

When making receivers it’s always a bit of a sod finding the bolt is to long or to short, so this is my solution to the problem, an adjustable bolt.

Make the bolt and then cut it in half , thread the two half’s and lock a thread into one of the half’s, add a nut and screw the of the half of the bolt on. You now have an adjustable bolt, if it is still to long then take a bit more off one end also with this idea you can tune the bolt for best performance.

Al

Slavia · Moderator

Alstone's method is beautiful, but just to throw an alternative into the mix: You could take about 0.050" off both ends of the "scab" (I would call it a bolt cam) and elongate the holes. The cam would then be adjustable. From experience it will probably slip when you tighten the screws, but you could obviate that by putting a feeler gauge in at the back while tightening. Alstone's method wouldn't have the "slippage" problem - you could increment/decrement the length simply by adding or subtracting fractions of a turn.

ZipSnipe · Veteran Member

Love it Al, very clever. I am actually planned to do something similar except it won't be adjustable. Instead it will have a hook shaped swivel piece in the center that will catch the cocking pin. This allows me to use the narrow cocking slot without having to mill out anymore into the breech.

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I am also planning on making the bolt larger diameter towards the back as the center area of the breech where the cocking handle is is wallowed out a little more than the diameter of the current bolt. This is causing some slight racking in the bolt handle its self.

I see why Crosman went with steel breeches. Aluminum is too soft and not a good slide bearing material.
The bolt wants to catch on the alum even though I have the bolt polished with nice smooth radius. This might get remedied when the breeches get anodized making the alum harder.

I did cycle the plastic breech and I seen that the seal on the probe part likes to catch in the barrel too like mine is currently doing.

I might have to redo another scab to get the bolt handle lock down position just right, but thats the cool thing about the scabs they are easy to make.

And then to make things worse the whole project might be delayed for 2 months as I wait for a new switch for my lathe to come in.

Alstone · Moderator & Site Supporter

BTW I do like the brass insert it kind of adds a bit of class to the breach.

Al

ZipSnipe · Veteran Member

Well I got it to the point I am ready to go test fire it. It is cycling pretty good. I put some light oil on the bolt and seemed to operate smoothly.

The only problem is it's FREEZING here in Florida !!!

Yeah Al I always have liked the look of brass and any kind of silvery polished metal.

I am really liking the titanium. Not easy to work with but man, once its polished up feels nice to the touch plus its freakin TITANIUM , just sounds tough

Alstone · Moderator & Site Supporter

Well Zip if you are going to use exotic materials such as Titanium you should replace the Brass with Gold and the screws for Silver.

I mean if your going to do it then do it properly. Smile

Al

ZipSnipe · Veteran Member

You are reading my mind Al !!!

I can use the bolt as is but as soon as my lathe is repaired I will be making a newer longer and a lil more fatter bolt for it.

Dang its cold :-(

Wait am I still in Florida?