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All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: mackeral5 on February 19, 2021, 06:10:25 PM

Title: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 19, 2021, 06:10:25 PM
3 bolts in the pic  The one in the middle is a Gen 1 Marauder .22 bolt that has been sleeved up to .25, I included it as a reference for length.  The two outer bolts, both made of stainless steel, are the bolts in question.  I recently picked these up, they were advertised as ".22 Marauder bolts."  But, they are too short for a Gen 1 or Gen 2 Marauder rifle breech.

Anyone know what they are for?  Since they are too short for my needs I will likely put them in the classifieds, but I do want to accurately describe them.

Thanks in advance.

(https://i.imgur.com/nBrwHDo.jpg)
Title: Re: What Crosman/Benjamin bolts are these?
Post by: RVaughn on February 19, 2021, 06:13:39 PM
P-Rod  bolts maybe 🤷‍♂️
Title: Re: What Crosman/Benjamin bolts are these?
Post by: dmeguy on February 19, 2021, 06:18:14 PM
They look like BNM bolts to me.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: Rick67 on February 19, 2021, 06:46:23 PM
They look like BNM bolts to me.

That is what I thought too.

BNM or GMAC.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 19, 2021, 07:45:48 PM
Great info, somewhat fragmented but I do appreciate the responses. 

When we say Prod---is a Prod bolt shorter than an Mrod?  that makes the most sense to me.

When we say GMAC or BNM----for what model gun?  Whatever gun it is, it would have a barrel mounted oring vs. probe mounted. 

I do know for certain, these will not work with an Mrod Rifle breech.

Thanks again.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: Rick67 on February 19, 2021, 08:07:57 PM
Do the L & R bolts have grooves for O-rings?

GMAC sells multi-shot breeches for the 22xx and 13xx guns (identical except for the breech screw location) but their bolts do have O-rings wound to it and not inside the barrel.
 
They also sell about the same breech for the QB’s, which I am not familiar with.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 19, 2021, 08:11:19 PM
Do the L & R bolts have grooves for O-rings?

GMAC sells multi-shot breeches for the 22xx and 13xx guns (identical except for the breech screw location) but their bolts do have O-rings wound to it and not inside the barrel.
 
They also sell about the same breech for the QB’s, which I am not familiar with.

The bolts on the left and right do NOT have oring grooves.  I see the GMAC multi shot breech/bolt and the similarity now that you've mentioned it. 
Title: Re: What Crosman/Benjamin bolts are these?
Post by: FuzzyGrub on February 19, 2021, 08:26:03 PM
Mike,

They are definitely not Prod/Fortitude bolts.  They are a little shorter, but also thinner than Mrod.  Picture is Fortitude 177 next to G2 Mrod 177.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 19, 2021, 08:44:23 PM
Mike,

They are definitely not Prod/Fortitude bolts.  They are a little shorter, but also thinner than Mrod.  Picture is Fortitude 177 next to G2 Mrod 177.

John, thanks for weighing in.  I really have no clue what these are for now.  I sent a message over to the seller, hopefully they will have better info.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: dmeguy on February 19, 2021, 09:17:19 PM
Here is my side bolt version BNM bolt with broken handle. You can seen the similarities. The BNM breeches fit the Disco/22xx/13xx series. They use a midblock with an o-ring to eliminate the need for an o-ring on the bolt but letting a standard Crosman barrel still work.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 19, 2021, 09:24:21 PM
Here is my side bolt version BNM bolt with broken handle. You can seen the similarities. The BNM breeches fit the Disco/22xx/13xx series. They use a midblock with an o-ring to eliminate the need for an o-ring on the bolt but letting a standard Crosman barrel still work.

That looks a lot like what I have.  Thanks for posting
Title: Re: What Crosman/Benjamin bolts are these?
Post by: Rick67 on February 20, 2021, 01:58:43 AM
Here is my side bolt version BNM bolt with broken handle. You can seen the similarities. The BNM breeches fit the Disco/22xx/13xx series. They use a midblock with an o-ring to eliminate the need for an o-ring on the bolt but letting a standard Crosman barrel still work.

Interesting!

Perhaps the GMAC bolts are w/o O-rings too?

Avator, our mod, has a GMAC breech, IIRIC.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: dmeguy on February 20, 2021, 11:00:08 AM


Interesting!

Perhaps the GMAC bolts are w/o O-rings too?

Avator, our mod, has a GMAC breech, IIRIC.

Looks very similar to BNM.


https://www.gmaccustomparts.com/epages/BT3197.sf/en_GB/?ObjectPath=/Shops/BT3197/Products/002-0600 (https://www.gmaccustomparts.com/epages/BT3197.sf/en_GB/?ObjectPath=/Shops/BT3197/Products/002-0600)
Title: Re: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 20, 2021, 11:15:18 AM
The bolts measure 3.6" overall length. 

Spacing of cocking lug hole and the bolt handle hole is 2.1" center to center.

Does this align with BNM measurements?
Title: Re: What Crosman/Benjamin bolts are these?
Post by: dmeguy on February 20, 2021, 11:19:41 AM
The bolts measure 3.6" overall length. 

Spacing of cocking lug hole and the bolt handle hole is 2.1" center to center.

Does this align with BNM measurements?


My BNM is a side cocker instead of a rear (they offered both options) so I don't really have anything to compare with.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: Rick67 on February 20, 2021, 01:00:50 PM
Scrutinizing it, it looks more like a BNM bolt; i.e., cocking bolt shape and its transition to tapering.

Senor Dmeguy could measure from the tip of the bolt probe to the cocking lug hole for your perusal, as that is what matters the most, I would surmise.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: dmeguy on February 20, 2021, 01:04:19 PM
Scrutinizing it, it looks more like a BNM bolt; i.e., cocking bolt shape and its transition to tapering.

Senor Dmeguy could measure from the tip of the bolt probe to the cocking lug hole for your perusal, as that is what matters the most, I would surmise.


I won't be home until late tonight to take a measurement but I'll keep an eye on this thread to see if someone else jumps in. If not, I'll post the measurement as soon as I get a chance tonight or more likely Sunday morning.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: Rick67 on February 20, 2021, 01:07:52 PM
(https://i.imgur.com/X7byqwc.gif)
Title: Re: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 20, 2021, 03:44:31 PM
Great stuff, thanks for everyone that chipped in. it seems like we are pretty close to confirming these as BNM.  Once confirmed I'll stick them in the classifieds for what I paid, ($25 shipped)  Perhaps there is a BNM owner out there looking for spare bolts...
Title: Re: What Crosman/Benjamin bolts are these?
Post by: dmeguy on February 20, 2021, 11:46:09 PM
Alright, I just measured from the muzzle end of the probe to the center of the cocking lug is 1.375". If I recall they did have an older design that was shorter, there were some posts about subpar muzzle energy because pellets were blocking the barrel port.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: mackeral5 on February 20, 2021, 11:54:01 PM
Alright, I just measured from the muzzle end of the probe to the center of the cocking lug is 1.375". If I recall they did have an older design that was shorter, there were some posts about subpar muzzle energy because pellets were blocking the barrel port.

Both of these measure 1.375 from tip of probe to center of cocking lug. 

I too recall the posts of BNM breech velocity issues related to probe/seating depth.
Title: Re: What Crosman/Benjamin bolts are these?
Post by: Rick67 on February 21, 2021, 02:19:56 PM
It seems the mystery has been solved  ;D

Mr. Dmeguy might purchase that from you then  ;D