--- title: "317 yards, 239 microseconds, under 46 inches: the three tour-only limits due 21 October, none of them for retail" url: "https://ifrothgolf.com/read/tour-only-equipment-rules-2028" type: "explainer" topic: "rules" author: "Tom Whitaker" published: "2026-09-25T07:00" publisher: "ifrothgolf" --- # 317 yards, 239 microseconds, under 46 inches: the three tour-only limits due 21 October, none of them for retail > The R&A and USGA want manufacturers' views on a ball, driver-face and club-length rule for elite events from 2028. Here is each one in the notice's own words, what it moves, and why every full-size driver we stock ships at 45.5 inches or longer. ## In short - The three proposals are tour-only Model Local Rules: a ball limit of 317.0 yards with no tolerance, a flat 239-microsecond CT tested before competition, and a length cap below 46 inches with no number set. Comments close 21 October 2026 and the rules could apply from January 2028. Nothing that conforms today stops conforming, but every full-size driver we stock ships at 45.5 inches or longer. On 21 September the R&A and USGA sent golf's equipment makers a two-page notice asking for comments, by **21 October 2026**, on three rules that would apply only at the top of the professional game. A ball limit of **317.0 yards** with no tolerance. A driver face tested before competition against a flat **239 microseconds**. And a maximum club length somewhere **below 46 inches**. None of them changes the Rules of Golf, and the notice says so in terms: if adopted, they "will not impact the conformance status of any conforming golf balls or golf clubs." They were requested by the PGA Tour and the DP World Tour, and they could be in force as early as January 2028. That is the news. What follows is what each one actually moves, which turns out to be less than the headlines suggest for the ball, more precise than anyone has put it for the driver, and a genuinely visible split between tour and retail for club length. ## The three rules, in the notice's own words All three are Model Local Rules, which means they are options a tournament committee can adopt in its conditions of competition, not changes to the equipment standards everyone else plays under. The notice lists them as (a), (b) and (c). **(a) The ball.** Requiring a ball on the List of Conforming Golf Balls "with an overall distance of 317.0 yards or less when tested by the USGA or The R&A." **(b) The driver.** Requiring a driver head "of a model and loft included on the List of Conforming Driver Heads, and when tested prior to competition has a maximum CT of 239 microseconds." **(c) Length.** "Restricting the maximum permitted length of all clubs (other than putters) to a limit that is less than the 46-inch limit imposed by MLR G-10." Two of those numbers are not new. 317 yards and 239 microseconds are today's limits. What the first two rules remove is the tolerance that sits on top of each one. The third is the only one that sets a new line, and it does not yet say where. ## The ball: three yards nobody outside the lab can see Under the current Overall Distance Standard, a ball tested at the governing bodies' launch conditions can travel 317 yards plus a 3-yard tolerance, so the working ceiling is 320. Rule (a) deletes the band. A ball that tests at 318 is conforming today and would be out at an event that adopts the rule. Here is the part to hold onto before you read any list of "balls that would be banned": there is no public way to make one. The List of Conforming Golf Balls records whether a model passed, not how far it went. The measured distances sit with the manufacturers and the governing bodies. Anyone naming specific models as sitting between 317.0 and 320.0 is guessing. It is also a much smaller rule than the rollback most people remember. The 2023 proposal changed the test itself, lifting the robot's clubhead speed to 127 mph, and was estimated to cost the longest hitters 14 to 15 yards. This one leaves the test alone and trims a tolerance. The full rollback is still parked until January 2030 at the earliest, which we covered when it was [delayed in June](https://ifrothgolf.com/read/golf-ball-rollback-delayed-2030). That piece argued the retreat made tour-only rules the likeliest destination. Three months later, here they are. For your own bag, nothing changes. A [Titleist Pro V1x](https://ifrothgolf.com/product/titleist-pro-v1x) on the conforming list today is on it tomorrow, and there is still no reason to buy, stockpile or avoid a ball because of any of this. If the question is which ball, the answer is still swing speed and short game, which is what [will your golf ball be banned](https://ifrothgolf.com/read/will-your-golf-ball-be-banned) walks through. ## The driver: the 18 microseconds that go CT, characteristic time, is the pendulum test for how springy a face is. The limit is 239 microseconds with an 18-microsecond tolerance, so a head can read up to 257 and still conform. We went through the test and why a face can creep over it in [our CT explainer](https://ifrothgolf.com/read/driver-ct-test-explained). Rule (b) changes two things at once. It removes the 18-microsecond buffer, and it moves the test to before competition. Today, roughly 30 drivers are tested at random at an event, measured against 257. Under this rule, a head reading 245 on a Wednesday would be a legal driver everywhere in golf except in the event that starts on the Thursday. No manufacturer publishes CT for any retail driver, so "does my driver pass 239?" has no public answer, and for a club golfer it doesn't need one. The practical consequence falls on the tour vans. This is our reading, not something the notice says: the obvious response is for tour heads to be built and sorted further from the line than they are now, which widens the gap between a tour-issue head and the one on the shelf. A [Titleist GT3](https://ifrothgolf.com/product/titleist-gt3-driver) bought at retail is a listed, conforming head before this proposal and after it. The rule is about which of those heads a tour player may put in play on a given week, not about which ones exist. ## Length: where tour and retail visibly split The tours already cap length. MLR G-10 lets a committee set a 46-inch maximum, against the 48 inches allowed under the general Equipment Rules, and the PGA Tour and other elite events have adopted it. At least one widely syndicated report said the new rule would bring the cap down from 48. It wouldn't. It would go below the 46 the tours already use. The notice gives no number. Any report of 45 or 45.5 inches is a guess. What we can say is where retail sits, because makers publish stock lengths. We checked the manufacturer spec pages for the nine full-size drivers we carry: **45.5 inches:** Titleist GT2, GT3 and GTS2, plus Ping's G440 Max and G440 K with the tour shaft options. **45.75 inches:** TaylorMade Qi4D and Qi10, the Callaway Quantum family and the Takomo Ignis D2. **46 inches:** Ping's G440 Max and G440 K with the stock ALTA CB Blue shaft. **All nine ship at 45.5 inches or longer.** Set the tour limit anywhere below 45.5 and every stock driver we sell would be longer than a tour player could use. The tour mostly got there on its own. GOLF.com's report on the proposal says most PGA Tour players already use drivers shorter than 45.5 inches, and many shorter than 45. The bags we track fit that, with one notable exception. [Scottie Scheffler](https://ifrothgolf.com/witb/scottie-scheffler)'s Qi4D is built to 45 inches. [Haeran Ryu](https://ifrothgolf.com/witb/haeran-ryu)'s Qi4D LS plays at 45.5. [Matt Fitzpatrick](https://ifrothgolf.com/witb/matt-fitzpatrick) is the outlier at 45.75, stock length for a TaylorMade and a quarter-inch clear of G-10 today. Only 3 of the 88 bags we track publish a driver length, so treat those as examples, not a count. One more wrinkle, and it is the manufacturers' own. TaylorMade's spec page for the [Qi4D](https://ifrothgolf.com/product/taylormade-qi4d-driver) lists 45.75 inches as stock and notes that it measures length differently from the USGA, so a custom build at that figure "may exceed the 46 limit as defined by the USGA." The inch on a spec sheet and the inch in the rulebook are not always the same inch. Any sub-46 tour limit will be measured the USGA's way, with the club at a 60-degree lie, which is exactly why a quarter-inch of spec-sheet headroom is not something to plan around. The [Ping G440 Max](https://ifrothgolf.com/product/ping-g440-max-driver) is the neat illustration of the point that length is a build decision, not a head decision. The same head is 46 inches with one stock shaft and 45.5 with another. A tour cap would be met the way Scheffler meets his, in the fitting bay. And the one driver-shaped club untouched by any plausible number: the mini driver. The [TaylorMade R7 Quad](https://ifrothgolf.com/product/taylormade-r7-quad-mini-driver) is 43.75 inches stock, as is Callaway's Ai Smoke 340 mini. If tour length caps do tighten, expect more of these off the tee, not fewer. ## The paragraph worth reading twice The three rules are near-term options. The notice also restates something longer-running, and it is the only part that could one day reach the driver you buy. An Area of Interest for a Model Local Rule on Club Performance Characteristics has been open since 16 March 2022, and the governing bodies say they continue to explore "driver design features that potentially could be regulated to reward centre impact position hits versus mishits." In plain terms, that is forgiveness. Perimeter weighting and high MOI are the whole pitch of most retail drivers. Nothing is proposed, it is still framed as a tour-level option, and the notice puts no date on it. But if you want one line from this document to keep an eye on, it is that one, not the three with numbers in them. ## What happens next Comments close on **21 October 2026**. Separately, the governing bodies say they will communicate again on the ball test within five months, so by around February 2027. The earliest any of the three rules could apply is **January 2028**, and only at events whose committees adopt them. The game-wide change to the ball test is **January 2030** at the earliest. ## Who should care If you play elite amateur golf and qualify into professional events, read the conditions of competition for every event you enter from 2028, because a committee can adopt any Model Local Rule it likes. If you follow the distance debate, this is the tour-only split the governing bodies spent three years saying they didn't want, arriving as three procedural options. Everyone else can skip it. Your driver, your ball and your shaft length are unaffected, and the only decision this should prompt is one worth making anyway: get your driver length fitted rather than taking stock, which is where the best players in the world already are. ## The takeaway The three proposals are tour-only Model Local Rules: a ball limit of 317.0 yards with no tolerance, a flat 239-microsecond CT tested before competition, and a length cap below 46 inches with no number set. Comments close 21 October 2026 and the rules could apply from January 2028. Nothing that conforms today stops conforming, but every full-size driver we stock ships at 45.5 inches or longer. ## FAQ ### What are the three new equipment rules proposed by the R&A and USGA? Three optional Model Local Rules for elite competitions: a ball on the conforming list with an overall distance of 317.0 yards or less, removing the current 3-yard tolerance; a driver head tested before competition with a maximum CT of 239 microseconds, removing the 18-microsecond tolerance; and a maximum length for all clubs except putters below the 46-inch limit in Model Local Rule G-10. They were set out in a notice to manufacturers on 21 September 2026. ### Will my driver or golf ball become illegal? No. The notice states that the proposed rules are not changes to the Equipment Rules and will not affect the conformance status of any conforming ball or club. They would apply only at events whose committees adopt them. ### What is the proposed maximum club length for tour players? The proposal does not give a number. It says only that the limit would be less than the 46-inch maximum under Model Local Rule G-10, which the PGA Tour already uses. Reports of 45 or 45.5 inches are speculation. For comparison, the nine full-size drivers we stock ship at between 45.5 and 46 inches. ### When could the tour-only equipment rules take effect? As early as January 2028. Manufacturers' comments are due by 21 October 2026. The separate game-wide change to the golf ball test will not happen before January 2030. ## Products mentioned - [TaylorMade Qi4D Driver](https://ifrothgolf.com/product/taylormade-qi4d-driver) · $700 approx — Stock at 45.75 inches, and TaylorMade's own spec page warns its measuring method differs from the USGA's. **Where to buy:** [Check price at Amazon](https://www.amazon.com/dp/B0G2PJM76C?tag=ifrothgolf-20&ascsubtag=md_taylormade-qi4d-driver) (affiliate link) - [Titleist GT3 Driver](https://ifrothgolf.com/product/titleist-gt3-driver) · $800 approx — Stock at 45.5 inches, tied for the shortest men's stock length among the full-size drivers we carry. **Where to buy:** [Check price at Amazon](https://www.amazon.com/dp/B0DHYS9TGK?tag=ifrothgolf-20&ascsubtag=md_titleist-gt3-driver) (affiliate link) - [PING G440 Max Driver](https://ifrothgolf.com/product/ping-g440-max-driver) · $450 approx — The one where the shaft sets the length: 46 inches with the stock ALTA, 45.5 with the tour options. **Where to buy:** [Check price at Amazon](https://www.amazon.com/dp/B0F6V82LDT?tag=ifrothgolf-20&ascsubtag=md_ping-g440-max-driver) (affiliate link) - [TaylorMade R7 Quad Mini Driver](https://ifrothgolf.com/product/taylormade-r7-quad-mini-driver) · $475 approx — 43.75 inches. The only driver-shaped club here that no plausible tour length cap goes near. **Where to buy:** [Check price at Amazon](https://www.amazon.com/dp/B0F2BTYL6S?tag=ifrothgolf-20&ascsubtag=md_taylormade-r7-quad-mini-driver) (affiliate link) · also stocked by TaylorMade - [Titleist Pro V1x](https://ifrothgolf.com/product/titleist-pro-v1x) · $60 approx — A conforming ball stays conforming. Whether any tour ball sits in the three-yard band is not public. **Where to buy:** [Check price at Amazon](https://www.amazon.com/dp/B0FH5NN34D?tag=ifrothgolf-20&ascsubtag=md_titleist-pro-v1x) (affiliate link) · also stocked by The Golf Shop Online --- Source: [ifrothgolf](https://ifrothgolf.com) — independent golf-gear editorial. Canonical URL: https://ifrothgolf.com/read/tour-only-equipment-rules-2028 Quote or cite freely with attribution and a link to the canonical URL. Affiliate disclosure: ifrothgolf may earn a commission on purchases made through the retailer links above, at no extra cost to the buyer. It never changes what we recommend. https://ifrothgolf.com/disclosure