diff --git a/gamma/rising_fmpcb_ui_delta.c b/gamma/rising_fmpcb_ui_delta.c
index fa84c28a..4a148e18 100644
--- a/gamma/rising_fmpcb_ui_delta.c
+++ b/gamma/rising_fmpcb_ui_delta.c
@@ -61,7 +61,7 @@ gamma_rising_fmpcb_ui_delta(fmpcb_t y, const fmpcb_t x, ulong n, ulong m, long p
     if (m == 0)
     {
         ulong m1, m2;
-        m1 = 0.04 * pow(2.0 * wp, 0.65);
+        m1 = 0.2 * pow(2.0 * wp, 0.4);
         m2 = n_sqrt(n);
         m = FLINT_MIN(m1, m2);
     }
diff --git a/gamma/rising_fmprb_ui_delta.c b/gamma/rising_fmprb_ui_delta.c
index bd726c28..07c13c65 100644
--- a/gamma/rising_fmprb_ui_delta.c
+++ b/gamma/rising_fmprb_ui_delta.c
@@ -96,7 +96,7 @@ gamma_rising_fmprb_ui_delta(fmprb_t y, const fmprb_t x, ulong n, ulong m, long p
     if (m == 0)
     {
         ulong m1, m2;
-        m1 = 0.04 * pow(wp, 0.65);
+        m1 = 0.2 * pow(wp, 0.4);
         m2 = n_sqrt(n);
         m = FLINT_MIN(m1, m2);
     }