OR3GUN Competition Spring Plunger
- Thread starter krbrand
- Start date
Tuflehundon
.270 WIN
If it works with the standard plunger, it should be fine.
In a way they did post it. I just had to read it carefully. The CSP reduces spring weight about 10% which prompted me to email them. When they replied about the new multi-use line of CSP the told me the new plunger would reduce weight only about 5% so I could use a steady diet of full power loads. Here is the quote on their website.
"In competition guns, there is a delicate balance between load weight and reliable cycling. The factory 930 is designed to run loads as heavy as magnum buckshot and turkey loads. If the competitor is willing to give up some of the heaviest end of the load spectrum, ground can be gained in the lighter end. "
"In competition guns, there is a delicate balance between load weight and reliable cycling. The factory 930 is designed to run loads as heavy as magnum buckshot and turkey loads. If the competitor is willing to give up some of the heaviest end of the load spectrum, ground can be gained in the lighter end. "
The decision to make a second CSP that produced closer to a factory spring weight was made a couple of weeks ago from continued customer feedback. While originally a 3-Gun geared part, the redesigned tail and spring mating surface seems to have appealed to more than the gun games crowd, so we looked at what changes needed to happen to make one that best applied to the rest of the 930/935 applications.
We had another run of the original version in progress and decided to tweak the column length to get us within 5% of stock spring weight on a small batch of them for testing, fully anticipating that a 5% version would be desired by a very small segment of 930 users. Traditionally, the first version of every part we've made has been geared toward the 3-Gun competitor, with any tweaked versions specific to hunters and defenders coming later. The current, original CSP in a 930 will without doubt allow you to run a wide assortment of loads, including full power 2.75" slugs and buckshot. Most 3-Gunners run 95% bird shot, with the rest mostly slugs and the rare need for something like a hot pheasant load for the occasional spinner. What should be avoided with a 10% spring weight reduction (for the sake of your receiver and other related recoil system parts) is a steady diet of 3" magnum rounds in a 930, or 3.5" magnum rounds in a 935. (For the sake of your cheek bones, 3.5" rounds should be avoided in a 935 anyway, but that's another topic.)
The relationship of bolt/carrier length and usage of the same recoil spring/tube combination by Mossberg adds spring weight to the 935 already, which is partly why many of them won't reliably run light loads. The 5% tweak made 1200 fPS bulk loads run quite reliably in our 935 test gun, which is a Grand Slam Turkey with the shortest barrel (and dwell time) offered in a 935 at 22". However, finding enough different 935s to draw any conclusion to the benefit of a 5% spring weight reduction isn't something we're geared up to do. Finding 930s set up for 3-Gun, no problem.
So, long story short, unless you will be regularly running more slugs/buckshot than birdshot and have not had any issues with your gun feeding lighter loads as stock, the original CSP will be the one to have in your gun. The upcoming Multi-Use version won't solve much in the way of spring weight related cycling issues (with such a minor spring weight reduction), but will have all of the benefits of capturing the spring and spurring a recoil system overhaul. It will also alleviate the concerns of those that envision possibly running a lot of magnum rounds in the future and not wanting the suggested limitation hanging over them. We may end up offering the Multi-Use version only within a Combo package to avoid causing buyers paralysis by analysis. If you already have a bunch of individual parts from such a combo that materializes and want only the Multi-Use CSP, we could probably liberate one for you once they are available in a few weeks.
William
http://www.OR3GUN.com
We had another run of the original version in progress and decided to tweak the column length to get us within 5% of stock spring weight on a small batch of them for testing, fully anticipating that a 5% version would be desired by a very small segment of 930 users. Traditionally, the first version of every part we've made has been geared toward the 3-Gun competitor, with any tweaked versions specific to hunters and defenders coming later. The current, original CSP in a 930 will without doubt allow you to run a wide assortment of loads, including full power 2.75" slugs and buckshot. Most 3-Gunners run 95% bird shot, with the rest mostly slugs and the rare need for something like a hot pheasant load for the occasional spinner. What should be avoided with a 10% spring weight reduction (for the sake of your receiver and other related recoil system parts) is a steady diet of 3" magnum rounds in a 930, or 3.5" magnum rounds in a 935. (For the sake of your cheek bones, 3.5" rounds should be avoided in a 935 anyway, but that's another topic.)
The relationship of bolt/carrier length and usage of the same recoil spring/tube combination by Mossberg adds spring weight to the 935 already, which is partly why many of them won't reliably run light loads. The 5% tweak made 1200 fPS bulk loads run quite reliably in our 935 test gun, which is a Grand Slam Turkey with the shortest barrel (and dwell time) offered in a 935 at 22". However, finding enough different 935s to draw any conclusion to the benefit of a 5% spring weight reduction isn't something we're geared up to do. Finding 930s set up for 3-Gun, no problem.
So, long story short, unless you will be regularly running more slugs/buckshot than birdshot and have not had any issues with your gun feeding lighter loads as stock, the original CSP will be the one to have in your gun. The upcoming Multi-Use version won't solve much in the way of spring weight related cycling issues (with such a minor spring weight reduction), but will have all of the benefits of capturing the spring and spurring a recoil system overhaul. It will also alleviate the concerns of those that envision possibly running a lot of magnum rounds in the future and not wanting the suggested limitation hanging over them. We may end up offering the Multi-Use version only within a Combo package to avoid causing buyers paralysis by analysis. If you already have a bunch of individual parts from such a combo that materializes and want only the Multi-Use CSP, we could probably liberate one for you once they are available in a few weeks.
William
http://www.OR3GUN.com
In case some reading this aren't up to speed on the CSP, here's our Recoil System Maintenance video from YouTube that shows why we primarily replace this part:
We are also working on a Part II of the video that will show in detail how to address any scoring or burrs in the recoil spring tube itself. We are finding this to be an important step in restoring a smooth recoil system that has been damaged by a spring burr.
William
http://www.OR3GUN.com
We are also working on a Part II of the video that will show in detail how to address any scoring or burrs in the recoil spring tube itself. We are finding this to be an important step in restoring a smooth recoil system that has been damaged by a spring burr.
William
http://www.OR3GUN.com
Greg B
.410
Is there any reason why a plunger with no spring reduction, just a spud to capture the end of the spring, couldn't be used?
As a standard type set-up. Not for competition.
Adding the spud would increase the overall length. But would that cause the plunger to bottom out during recoil?
As a standard type set-up. Not for competition.
Adding the spud would increase the overall length. But would that cause the plunger to bottom out during recoil?
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The issue wouldn't be one of the plunger bottoming out under recoil, but the weight of the part becomes an issue.
The factory Mossberg plunger is hollowed out, while ours (in order to provide a rounded tail) is not. From a machining standpoint, it becomes a multiple step process to create a profile that both captures the spring and is hollowed out enough to keep the weight within acceptable parameters.
If an even stronger spring weight were desired for some reason, the best part to alter for it would be the one on the other end of the spring.
William
http://www.OR3GUN.com
The factory Mossberg plunger is hollowed out, while ours (in order to provide a rounded tail) is not. From a machining standpoint, it becomes a multiple step process to create a profile that both captures the spring and is hollowed out enough to keep the weight within acceptable parameters.
If an even stronger spring weight were desired for some reason, the best part to alter for it would be the one on the other end of the spring.
William
http://www.OR3GUN.com
With machining, double the pieces usually equals double the cost.
Also, having separate moving parts under that much regular impact leaves too many places for things to go wrong inside the recoil assembly.
We have a supplemental part in process that will provide some more options for those wanting to tune the recoil spring weight up to and beyond the factory.
Around SHOT Show there will be a number of new parts from us.
William
http://www.OR3GUN.com
Also, having separate moving parts under that much regular impact leaves too many places for things to go wrong inside the recoil assembly.
We have a supplemental part in process that will provide some more options for those wanting to tune the recoil spring weight up to and beyond the factory.
Around SHOT Show there will be a number of new parts from us.
William
http://www.OR3GUN.com
Greg B
.410
Oh I hear ya. Time and material is money in the shop.
Just this morning, I set-up, programmed, and started a job running on the Fadal. While that's working, since I have cycle time, I set up the surface grinder and got that running.
If I was really ambitious, I'd get a job going on one of the Bridgeports. But hey, it's Friday.
Just this morning, I set-up, programmed, and started a job running on the Fadal. While that's working, since I have cycle time, I set up the surface grinder and got that running.
If I was really ambitious, I'd get a job going on one of the Bridgeports. But hey, it's Friday.
That does sound awfully ambitious for a Friday.
I'm packing for what amounts to a BUG match tomorrow and am midway through putting sights on the gun I was planning to use. I'm half considering running without sights at all and seeing if anyone (including myself) notices.
William
http://www.OR3GUN.com
I'm packing for what amounts to a BUG match tomorrow and am midway through putting sights on the gun I was planning to use. I'm half considering running without sights at all and seeing if anyone (including myself) notices.
William
http://www.OR3GUN.com
got a question.... is there a SP thats oem weight...not the ESR...
the CSP is lighter ( don't know how much? ) and has 10% lower ESR
the Multiuse Sp is 10% heavier than oem ans has 5% lower ESR
why not a oem weight SP? has the company made some test with a oem weight SP and lower ESR to see how it does with light loads and heavy loads?
i mean something in the oem weight with 7-8 lower ESR can get away with both loads..?
the CSP is lighter ( don't know how much? ) and has 10% lower ESR
the Multiuse Sp is 10% heavier than oem ans has 5% lower ESR
why not a oem weight SP? has the company made some test with a oem weight SP and lower ESR to see how it does with light loads and heavy loads?
i mean something in the oem weight with 7-8 lower ESR can get away with both loads..?
Here's how the part weights and Effective Spring Weight break down:
13.75 grams - OEM Plunger (Average of 3 as new) 0% change in effective spring rate
13.23 grams - OR3GUN Competition Plunger (anodized version) ~ 10% reduction in effective spring rate
15.06 grams - OR3GUN Multi-Use Plunger (anodized version) ~ 5% reduction in effective spring rate
When you look at the differences, they are minor in relation to the entire cycling part weight (bolt, slide, link) and the spring weight itself is the primary difference. A change in charging handle for the bolt makes a bigger change in cycling part weight than the different plungers. The Competition version is only about 1/2 gram lighter than the factory plunger.
The release of our Adjustable Spring Retainer (ASR) during SHOT Week, addressed the tuning ability of the Competition Spring Plunger to get that magic ~ 7-8% reduction in Effective Spring Weight. This part replaces the plastic, factory 'Return Spring Retainer' that holds the back of the spring in the gun with one that has 4 positions (1 lighter, 3 heavier) that allow additional tuning of the Effective Spring Rate. This will allow users to find the right combination for their given selection of loads and the tolerances of their gun. The Competition ASR has been designed first (as usual) for the realm of 3-Gun competition, where a 930 owner typically favors certain exact loads for clay stages, knock-over steel, poppers and spinners, then finds a low-recoil slug that sights in well with their gun. Once they get all of these standard competition loads dialed in, they typically buy them by the case load and that is all their gun will ever shoot. Set your 930 up to run them in all conditions and you'll never look back.
We're always taking customer feedback into account when designing new products and versions of products. As a company focused heavily on competition, other applications are sometimes a few months behind and require doing things with a different perspective in mind. This forum thread is an example of how a product for the same gun can evolve to the specifics of different markets for the same gun. The Multi-Use Plunger came into production as a result of the vast majority of 930/935 owners simply wanting to reliably shoot inexpensive bulk packs, but still have the gun survive the heavy stuff. Cowboy loads were certainly off the table, but a box of full power slugs once in a while was still on. Shorter barrels mean shorter dwell time, but that is the case on ALL loads, so the Multi-Use Plunger is extremely versatile.
The power factor (load weight x velocity) of common shotgun shells range from 375 (Winchester AA 980 FPS) to 1138 (Winchester 3.5" Turkey). From the factory, the 375 PF stuff simply won't run at all in a 935 and won't reliably cycle the 930. It is a contest in a 935 (when shooting 1138 PF loads) to see whether your face or gun gets beat up first. It simply isn't practical for any autoloading shotgun to operate both of these extremes reliably without changes to the hardware that favor one end or the other. As expected, most autoloaders run most reliably on the average load. Some of the more expensive inertial guns conveniently gloss over the fact that you will need upwards of 1250 FPS to reliably cycle them. We keep hearing how much more reliable they are, but the fine print reminds us that paying twice as much for your ammo can sometimes have that effect. The 930's dual gas system can run a wider range than most, but it helps to pick an end of the spectrum to tune for.
We have been in testing for a while on a 3rd captured-spring plunger version (@ 13.26 grams) in combination with a modified version of the ASR for possible inclusion in our upcoming Field Combo 2.0 that should be available around April. It would allow a fairly simple choice between ~ 10% reduction and 0% reduction in Effective Spring Rate, with the intent that the owner would be able to reliably run a bunch of bulk loads in practice and change the setting for full spring weight before they head out to hunt with full boat loads. Removing the recoil pad (2 screws), inserting a punch and rotating a 'dial' between two positions would be the complete changeover process to go between the extremes. That's not a very practical proposition for 3-Gun competition from stage to stage (though not too much more work than a choke change), nor does it make much sense for someone running loads that all fall into the average range. It DOES make sense for someone that does two remarkably different tasks with the same gun and has a few minutes between those tasks to set it up properly for each.
Again, we're always looking at ways to accommodate the various ways the 930/935 is used within the practical limitations of physics and how the platform deals with those limitations.
William
http://www.OR3GUN.com
13.75 grams - OEM Plunger (Average of 3 as new) 0% change in effective spring rate
13.23 grams - OR3GUN Competition Plunger (anodized version) ~ 10% reduction in effective spring rate
15.06 grams - OR3GUN Multi-Use Plunger (anodized version) ~ 5% reduction in effective spring rate
When you look at the differences, they are minor in relation to the entire cycling part weight (bolt, slide, link) and the spring weight itself is the primary difference. A change in charging handle for the bolt makes a bigger change in cycling part weight than the different plungers. The Competition version is only about 1/2 gram lighter than the factory plunger.
The release of our Adjustable Spring Retainer (ASR) during SHOT Week, addressed the tuning ability of the Competition Spring Plunger to get that magic ~ 7-8% reduction in Effective Spring Weight. This part replaces the plastic, factory 'Return Spring Retainer' that holds the back of the spring in the gun with one that has 4 positions (1 lighter, 3 heavier) that allow additional tuning of the Effective Spring Rate. This will allow users to find the right combination for their given selection of loads and the tolerances of their gun. The Competition ASR has been designed first (as usual) for the realm of 3-Gun competition, where a 930 owner typically favors certain exact loads for clay stages, knock-over steel, poppers and spinners, then finds a low-recoil slug that sights in well with their gun. Once they get all of these standard competition loads dialed in, they typically buy them by the case load and that is all their gun will ever shoot. Set your 930 up to run them in all conditions and you'll never look back.
We're always taking customer feedback into account when designing new products and versions of products. As a company focused heavily on competition, other applications are sometimes a few months behind and require doing things with a different perspective in mind. This forum thread is an example of how a product for the same gun can evolve to the specifics of different markets for the same gun. The Multi-Use Plunger came into production as a result of the vast majority of 930/935 owners simply wanting to reliably shoot inexpensive bulk packs, but still have the gun survive the heavy stuff. Cowboy loads were certainly off the table, but a box of full power slugs once in a while was still on. Shorter barrels mean shorter dwell time, but that is the case on ALL loads, so the Multi-Use Plunger is extremely versatile.
The power factor (load weight x velocity) of common shotgun shells range from 375 (Winchester AA 980 FPS) to 1138 (Winchester 3.5" Turkey). From the factory, the 375 PF stuff simply won't run at all in a 935 and won't reliably cycle the 930. It is a contest in a 935 (when shooting 1138 PF loads) to see whether your face or gun gets beat up first. It simply isn't practical for any autoloading shotgun to operate both of these extremes reliably without changes to the hardware that favor one end or the other. As expected, most autoloaders run most reliably on the average load. Some of the more expensive inertial guns conveniently gloss over the fact that you will need upwards of 1250 FPS to reliably cycle them. We keep hearing how much more reliable they are, but the fine print reminds us that paying twice as much for your ammo can sometimes have that effect. The 930's dual gas system can run a wider range than most, but it helps to pick an end of the spectrum to tune for.
We have been in testing for a while on a 3rd captured-spring plunger version (@ 13.26 grams) in combination with a modified version of the ASR for possible inclusion in our upcoming Field Combo 2.0 that should be available around April. It would allow a fairly simple choice between ~ 10% reduction and 0% reduction in Effective Spring Rate, with the intent that the owner would be able to reliably run a bunch of bulk loads in practice and change the setting for full spring weight before they head out to hunt with full boat loads. Removing the recoil pad (2 screws), inserting a punch and rotating a 'dial' between two positions would be the complete changeover process to go between the extremes. That's not a very practical proposition for 3-Gun competition from stage to stage (though not too much more work than a choke change), nor does it make much sense for someone running loads that all fall into the average range. It DOES make sense for someone that does two remarkably different tasks with the same gun and has a few minutes between those tasks to set it up properly for each.
Again, we're always looking at ways to accommodate the various ways the 930/935 is used within the practical limitations of physics and how the platform deals with those limitations.
William
http://www.OR3GUN.com
Tuflehundon
.270 WIN
Check your piston for burrs. Were exactly is it being scratched?