Possibly they do not ship to your location? Might want to contact them directly and see if that's the case.. You would think they would just state that but not sure.
OR3GUN Marine Spacer Tube for Mossberg 930/935
- Thread starter DHonovich
- Start date
Possibly they do not ship to your location? Might want to contact them directly and see if that's the case.. You would think they would just state that but not sure.
RicksOne
.410
I don't live in a wet area but I plan on taking my Blackie with me to many different places and will be dealing with what ever conditions are thrown at me. I figured it was cheap insurance and I might get to run some less expensive low-brass ammo with it. Thats what the local indoor range uses. It was shipped right away and made it to So Cal from Oregon in under 4 days. My only issue is with USPS... their tracking program sucks. So far dealing with OR3GUN has been great... I can't say how the tube has performed yet but I'm sure its awesome according to the review I've read here. I can't wait to try it out. Thanks everyone here. I've been learning a lot from the posts here.
I wanted to let you all know how much we appreciate your support. When we started out trying to solve our own winter cycling problems in the dark for the summer Crimson Trace Midnight 3-Gun match, we never dreamed we would be solving it for so many others. I've got a bunch more to share with you guys about how we got here and where we are going, but I want you to know that we're going to be an active presence on the forum here to help out with the 930 we've all become so attached to. Over years of matches with 8+ Mossberg 930s in use on our team, we've seen it all and will do our best to help out in the various troubleshooting threads as they pop up.
Since it's coming up on SHOT show time, I wanted you guys to be among the first to see 'version 2.0' of the Marine Spacer Tube. We had a singular focus of 3-Gun competition when we designed 1.0 and wanted to make the second version tailored to the hunting and defensive models of the 930/935 and incorporate the machining quality feedback we were getting at the same time. We also heard concerns about using it with Magnum loads and slugs. Even though we actually BROKE an 930 SPX with a case of 1600 FPS slugs and didn't phase the MST, for our new version we brought the part up to factory weight to ensure it would cooperate with Magnum loads in the 930/935. We also refined the manufacturing methods into a three machine ordeal that results in a much smoother finish. We also gave it a less '3-gunny' looking Storm Gray anodizing with a Teflon coating incorporated into the process.
Here's the first public look at what we've done:
The above is actually a color photo (as you may catch from the red fiber optic sight), but you can see we tried to make it blend in to the urban landscape. The actual color is a bit darker than the image appears on screen and is closer to Magpul's Stealth Gray (which the shotgun is Duracoated to match). The sticker you see is a limited edition grayscale version of our 'mag tube wrap' team decal that we made to live on our team's personal guns. While the blue one shown below is what ships with all Marine Spacer Tubes going forward, we are including the gray version too with all on-line pre-orders of the new Storm Gray version through the end of the 2015 SHOT show.
Thanks again guys for the support and let us know what we can do to help out. We've got a bunch of other things in the works, including a couple of 930 parts that aren't the MST. There are a couple of hints about them on our website and we'll make sure to post specifics here first.
As to the inability to order from outside the US, that is due to the maze of ITAR and export regulations that need sorted out. We are trying to get set up through a distributor that can work through it with us. Initial research indicates we are clear on the ITAR front as we are told the Mossberg 930 doesn't fit the ITAR definition of a 'combat shotgun', but there would still be a raft of export regulations that a distributor is the best route through.
I just finished a 150+ round night match practice with the SPX and took it apart to get some pictures of how well the MST does its job. Most of the shooting was done at dew point, so the gas system's contribution was nice and muddy. I'll try to get a thread started in our sponsor forum soon and link to it here once it is up.
- William
http://www.OR3GUN.com
Since it's coming up on SHOT show time, I wanted you guys to be among the first to see 'version 2.0' of the Marine Spacer Tube. We had a singular focus of 3-Gun competition when we designed 1.0 and wanted to make the second version tailored to the hunting and defensive models of the 930/935 and incorporate the machining quality feedback we were getting at the same time. We also heard concerns about using it with Magnum loads and slugs. Even though we actually BROKE an 930 SPX with a case of 1600 FPS slugs and didn't phase the MST, for our new version we brought the part up to factory weight to ensure it would cooperate with Magnum loads in the 930/935. We also refined the manufacturing methods into a three machine ordeal that results in a much smoother finish. We also gave it a less '3-gunny' looking Storm Gray anodizing with a Teflon coating incorporated into the process.
Here's the first public look at what we've done:
The above is actually a color photo (as you may catch from the red fiber optic sight), but you can see we tried to make it blend in to the urban landscape. The actual color is a bit darker than the image appears on screen and is closer to Magpul's Stealth Gray (which the shotgun is Duracoated to match). The sticker you see is a limited edition grayscale version of our 'mag tube wrap' team decal that we made to live on our team's personal guns. While the blue one shown below is what ships with all Marine Spacer Tubes going forward, we are including the gray version too with all on-line pre-orders of the new Storm Gray version through the end of the 2015 SHOT show.
Thanks again guys for the support and let us know what we can do to help out. We've got a bunch of other things in the works, including a couple of 930 parts that aren't the MST. There are a couple of hints about them on our website and we'll make sure to post specifics here first.
As to the inability to order from outside the US, that is due to the maze of ITAR and export regulations that need sorted out. We are trying to get set up through a distributor that can work through it with us. Initial research indicates we are clear on the ITAR front as we are told the Mossberg 930 doesn't fit the ITAR definition of a 'combat shotgun', but there would still be a raft of export regulations that a distributor is the best route through.
I just finished a 150+ round night match practice with the SPX and took it apart to get some pictures of how well the MST does its job. Most of the shooting was done at dew point, so the gas system's contribution was nice and muddy. I'll try to get a thread started in our sponsor forum soon and link to it here once it is up.
- William
http://www.OR3GUN.com
RicksOne
.410
I wanted to let you all know how much we appreciate your support. When we started out trying to solve our own winter cycling problems in the dark for the summer Crimson Trace Midnight 3-Gun match, we never dreamed we would be solving it for so many others. I've got a bunch more to share with you guys about how we got here and where we are going, but I want you to know that we're going to be an active presence on the forum here to help out with the 930 we've all become so attached to. Over years of matches with 8+ Mossberg 930s in use on our team, we've seen it all and will do our best to help out in the various troubleshooting threads as they pop up.
Since it's coming up on SHOT show time, I wanted you guys to be among the first to see 'version 2.0' of the Marine Spacer Tube. We had a singular focus of 3-Gun competition when we designed 1.0 and wanted to make the second version tailored to the hunting and defensive models of the 930/935 and incorporate the machining quality feedback we were getting at the same time. We also heard concerns about using it with Magnum loads and slugs. Even though we actually BROKE an 930 SPX with a case of 1600 FPS slugs and didn't phase the MST, for our new version we brought the part up to factory weight to ensure it would cooperate with Magnum loads in the 930/935. We also refined the manufacturing methods into a three machine ordeal that results in a much smoother finish. We also gave it a less '3-gunny' looking Storm Gray anodizing with a Teflon coating incorporated into the process.
Here's the first public look at what we've done:
The above is actually a color photo (as you may catch from the red fiber optic sight), but you can see we tried to make it blend in to the urban landscape. The actual color is a bit darker than the image appears on screen and is closer to Magpul's Stealth Gray (which the shotgun is Duracoated to match). The sticker you see is a limited edition grayscale version of our 'mag tube wrap' team decal that we made to live on our team's personal guns. While the blue one shown below is what ships with all Marine Spacer Tubes going forward, we are including the gray version too with all on-line pre-orders of the new Storm Gray version through the end of the 2015 SHOT show.
Thanks again guys for the support and let us know what we can do to help out. We've got a bunch of other things in the works, including a couple of 930 parts that aren't the MST. There are a couple of hints about them on our website and we'll make sure to post specifics here first.
As to the inability to order from outside the US, that is due to the maze of ITAR and export regulations that need sorted out. We are trying to get set up through a distributor that can work through it with us. Initial research indicates we are clear on the ITAR front as we are told the Mossberg 930 doesn't fit the ITAR definition of a 'combat shotgun', but there would still be a raft of export regulations that a distributor is the best route through.
I just finished a 150+ round night match practice with the SPX and took it apart to get some pictures of how well the MST does its job. Most of the shooting was done at dew point, so the gas system's contribution was nice and muddy. I'll try to get a thread started in our sponsor forum soon and link to it here once it is up.
- William
http://www.OR3GUN.com
I wish you woulda mentioned this a week ago. Me having a personal defense 930 I would have waited for the appropriate tube.
It's not that the original is suddenly an inappropriate tube.
Remember, the original version outlasted a 930 itself with a case of magnum slugs, after about 1000 rounds of mixed magnum buckshot, high-brass bird shot and others. The Multi-Use MST is now an upgraded design for that purpose, rather than competition with light loads.
You could always get the new one and carry the original around in your range bag to be another 930 owner's hero some day.
Tell you what, we'll come up with something for SHOT show week to help owners of the Competition version add the new Multi-Use version to their toolbox. We'll get an email out to prior purchasers with the details early next week.
- William
http://www.OR3GUN.com
Remember, the original version outlasted a 930 itself with a case of magnum slugs, after about 1000 rounds of mixed magnum buckshot, high-brass bird shot and others. The Multi-Use MST is now an upgraded design for that purpose, rather than competition with light loads.
You could always get the new one and carry the original around in your range bag to be another 930 owner's hero some day.
Tell you what, we'll come up with something for SHOT show week to help owners of the Competition version add the new Multi-Use version to their toolbox. We'll get an email out to prior purchasers with the details early next week.
- William
http://www.OR3GUN.com
Looking forward to it!!!
NorCal707
.22LR
I've experienced several failure to fully eject malfunctions shooting magnum slugs since installing your original MST in my JM Pro 24. The hulls are getting caught/jammed between the bolt and the front of the ejection port. I haven't had a single problem shooting cheap lower power 2-3/4" loads for clays.
I am not/will not be using my gun in competition but did buy it primarily as a high-capacity Defensive weapon. If the re-designed Multi-Use version is what I need to ensure reliable cycling of Hi-Base/Magnum loads, I'd like to return the two Competition versions I bought for my and my Brothers JM Pro's and exchange them for the Multi-Use version.
I’m afraid next week’s ‘early adopter deal’ won’t be anywhere near as exciting as a trade-in program, which isn’t really feasible with a firearm component. Glock probably won’t have my 9mm single-stack ready either, but we’ll hopefully still make it through the week
The ‘new’ version of the MST was originally going to be a nod to hunter requests for the same part in dark green with machining refinements. There is nothing about the original that warranted functional changes to the weight of the part. But, since we were creating a version for a new market we saw no compelling reason to NOT make the change. Our extensive testing showed (as we further experimented with part weight) that the weight alone was not responsible for the faster cycling. We gradually enlarged the outside diameter to a comfortable fitment within the tube/barrel spacing against the 935 for added strength and this brought the part back to OEM weight. By skipping green and combining the features, we simply avoided creating a third version for the defense market by creating the single Multi-Use version in a neutral Storm Gray.
Now we get to the science part of why the weight has proven far less relevant to the design than the reduction of friction (hydraulic and otherwise) found in both MST models. The moving components in the gas system weigh +/- 140 grams. The difference in spacer tubes is +/- 3.5 grams, about 10% of the spacer tube weight or about 2.5% of the total reciprocating weight. This reciprocating weight is pushed against a pusher spring weight of +/- 3000 grams. This effective reciprocating weight difference (before you even get to the bolt, carrier and recoil spring) is negligible. Unfortunately, the change of MST versions won’t fix, nor is it causing, the issue you are having with slugs in a JM Pro.
With all of that out of the way, let’s get to diagnosing what IS actually going on with your gun. You have one of two things I suspect are going on that combine to throw you fits with slugs.
First, empty slug hulls (depending on brand and type) are typically the longest type of shell you will find because they aren’t crimped, but rolled and folded inside the shell. Many 2.75” slugs won’t fit in 2.75" shell caddies and many 3” slugs won’t fit reliably through the ejection port of many 3” autoloaders. Many have found a good rule of thumb to be running 3” slugs only through 3.5” guns for this reason. The longer shell will also hang up on the chamber ledge (in absence of a forcing cone modification) and be harder to extract. Check the empty hulls on your magnum slug rounds and see how much clearance there is with the bolt locked back. If the rounded corners of the ejection port don’t have plenty of clearance, you will have these problems in cycling. I don’t have any 930s within reach for a few days and may not have your specific load on hand, otherwise I could check this for you.
The other issue involves the design of the JM Pro itself. Mossberg has (and it is believed continues to) use differing weights of secondary gas system springs in different 930/935 models. They used to seem somewhat based on dwell time, or simply put, the amount of barrel past the gas ports on a specific model. It seems of late that they may be based on the intended market for the gun. The JM Pro is without a doubt designed for competition and its gas system should be tuned from Mossberg for lighter loads. The secondary gas system spring is visible through the large vents directly in front of where the gas piston goes into the barrel. These used to be different colors. My 24” turkey model had a black one, readily choked on lighter loads (pre MST) and ate turkey shells like candy. My JM Pro has a blue one and seems less happy about magnum buckshot and slugs based on the scoring of the tube by the secondary gas system. My SPX also has a black one and the same problem. The problem revolves around the pressure level that the secondary gas system opens and vents the pressure. The MST will only help in making this more consistent and less effected by resistance from the primary gas system.
Hopefully that gives you some things to look for. Feel free to PM me what shells you were using and I’ll see if I can replicate the problem next week.
- William
http://www.OR3GUN.com
The ‘new’ version of the MST was originally going to be a nod to hunter requests for the same part in dark green with machining refinements. There is nothing about the original that warranted functional changes to the weight of the part. But, since we were creating a version for a new market we saw no compelling reason to NOT make the change. Our extensive testing showed (as we further experimented with part weight) that the weight alone was not responsible for the faster cycling. We gradually enlarged the outside diameter to a comfortable fitment within the tube/barrel spacing against the 935 for added strength and this brought the part back to OEM weight. By skipping green and combining the features, we simply avoided creating a third version for the defense market by creating the single Multi-Use version in a neutral Storm Gray.
Now we get to the science part of why the weight has proven far less relevant to the design than the reduction of friction (hydraulic and otherwise) found in both MST models. The moving components in the gas system weigh +/- 140 grams. The difference in spacer tubes is +/- 3.5 grams, about 10% of the spacer tube weight or about 2.5% of the total reciprocating weight. This reciprocating weight is pushed against a pusher spring weight of +/- 3000 grams. This effective reciprocating weight difference (before you even get to the bolt, carrier and recoil spring) is negligible. Unfortunately, the change of MST versions won’t fix, nor is it causing, the issue you are having with slugs in a JM Pro.
With all of that out of the way, let’s get to diagnosing what IS actually going on with your gun. You have one of two things I suspect are going on that combine to throw you fits with slugs.
First, empty slug hulls (depending on brand and type) are typically the longest type of shell you will find because they aren’t crimped, but rolled and folded inside the shell. Many 2.75” slugs won’t fit in 2.75" shell caddies and many 3” slugs won’t fit reliably through the ejection port of many 3” autoloaders. Many have found a good rule of thumb to be running 3” slugs only through 3.5” guns for this reason. The longer shell will also hang up on the chamber ledge (in absence of a forcing cone modification) and be harder to extract. Check the empty hulls on your magnum slug rounds and see how much clearance there is with the bolt locked back. If the rounded corners of the ejection port don’t have plenty of clearance, you will have these problems in cycling. I don’t have any 930s within reach for a few days and may not have your specific load on hand, otherwise I could check this for you.
The other issue involves the design of the JM Pro itself. Mossberg has (and it is believed continues to) use differing weights of secondary gas system springs in different 930/935 models. They used to seem somewhat based on dwell time, or simply put, the amount of barrel past the gas ports on a specific model. It seems of late that they may be based on the intended market for the gun. The JM Pro is without a doubt designed for competition and its gas system should be tuned from Mossberg for lighter loads. The secondary gas system spring is visible through the large vents directly in front of where the gas piston goes into the barrel. These used to be different colors. My 24” turkey model had a black one, readily choked on lighter loads (pre MST) and ate turkey shells like candy. My JM Pro has a blue one and seems less happy about magnum buckshot and slugs based on the scoring of the tube by the secondary gas system. My SPX also has a black one and the same problem. The problem revolves around the pressure level that the secondary gas system opens and vents the pressure. The MST will only help in making this more consistent and less effected by resistance from the primary gas system.
Hopefully that gives you some things to look for. Feel free to PM me what shells you were using and I’ll see if I can replicate the problem next week.
- William
http://www.OR3GUN.com
Would a trade in work for an unused one? I just haven't had time to even install it yet. ;-D
Edit, DOH, just saw the email and ordered the new version. Guess I should have checked my email first thing. That's what I get for sitting out on the ice all weekend.
Edit, DOH, just saw the email and ordered the new version. Guess I should have checked my email first thing. That's what I get for sitting out on the ice all weekend.
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The secondary gas system was working overtime with all of those slugs. By the time it was done with the case of slugs the 930 wouldn't cycle bird shot anymore. The spring had developed a burr and dug into the magazine tube as it cycled. The secondary gas system spring had shredded the magazine tube to where it no longer sealed well enough to provide proper pressure for the gas system.
The gun was taken apart and the magazine tube was smoothed as best as it could be and polished up, but it was just too scored and (then) undersized to maintain a proper seal.
@OR3GUN I'd really like to see you, or anyone, come up with a replacement pusher for the 930/935. I've recall seeing that someone worked on an alum one but it never really worked well because it was heavier than the plastic. The part really seems to be the weakest link and one that there is no other option for.
While I have not had issues with this part, I've seen a LOT of them with cracks so I assume it's just a matter of time. If you could pull it off I know there are a few of us here that would be all over it.
I love my 930 but there are admittedly a few places where it can be improved.
While I have not had issues with this part, I've seen a LOT of them with cracks so I assume it's just a matter of time. If you could pull it off I know there are a few of us here that would be all over it.
I love my 930 but there are admittedly a few places where it can be improved.
The pusher is farther down the list for us at this point. This is mostly because the only one we ever saw damaged had other problems that caused the gun to be way over-gassed, contributing to the cracked pusher. The pusher still worked, it had just 'wowed' out a bit and started wearing against the forearm retainer. Regular spring replacement is also a good plan.
The forearm retainer, however, IS our next part. By mid February the first of our T6 alloy 'Enhanced Forearm Retainer' will be out. This will keep the pusher aligned better if it does crack, but the primary reason for it is to close the gap between the forend/receiver (better for quad loading) and provide a much stronger part for ramping to meet modified forends for the 3-Gun shooters. It has 'user tunable' tangs that raise the forend higher up the barrel/receiver and eliminate the gap.
It will also eliminate the play in the forend and keep the retaining rails inside the forend off of the pusher in the first place. This is another source of drag on the gas system on 'abused' guns.
I'll get something up in our Sponsor Area in the next few days with pictures of the difference it makes. For now, I've got to pack up for a night shotgun match tomorrow. More proving ground for the Marine Spacer Tube.
- William
http://www.OR3GUN.com
The forearm retainer, however, IS our next part. By mid February the first of our T6 alloy 'Enhanced Forearm Retainer' will be out. This will keep the pusher aligned better if it does crack, but the primary reason for it is to close the gap between the forend/receiver (better for quad loading) and provide a much stronger part for ramping to meet modified forends for the 3-Gun shooters. It has 'user tunable' tangs that raise the forend higher up the barrel/receiver and eliminate the gap.
It will also eliminate the play in the forend and keep the retaining rails inside the forend off of the pusher in the first place. This is another source of drag on the gas system on 'abused' guns.
I'll get something up in our Sponsor Area in the next few days with pictures of the difference it makes. For now, I've got to pack up for a night shotgun match tomorrow. More proving ground for the Marine Spacer Tube.
- William
http://www.OR3GUN.com
We actually have a couple of local gun stores in the area that handle retail sales for us.
We are on the coast, in Coos Bay. Otherwise, you would be ahead to order direct.
- William
http://www.OR3GUN.com
We are on the coast, in Coos Bay. Otherwise, you would be ahead to order direct.
- William
http://www.OR3GUN.com